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Example Questions
Example Question #11 : Earth And Space Sciences
According to the Big Bang theory, which proposes that the universe is roughly 13.7 billion years old, all matter and energy were at one time compressed into a single microscopic point. This point then exploded outward in all directions in a rapid expansion. The expansion has continued to the present day, which has allowed matter to cool to a state at which stable atomic components can form. The Big Bang theory proposes that our universe is finite in age, and since nothing can travel faster than the speed of light, there exists a cosmological horizon, which is the maximum distance light or energy could have travelled since the occurrence of the Big Bang. Since the universe is still expanding, however, regions of space that are visible from our vantage point are not within each other's cosmological horizons. For example, if galaxy A is 10 billion light years away from us, and galaxy B is 10 billion light years away from us in the opposite direction, there is a total distance of 20 billion light years between them. The universe has only existed long enough for light, energy, or information to travel 13.7 billion light years between them; thus, it is not possible for any contact to have been made between the two galaxies. Yet, even these vastly separated regions of space have been observed to be extremely homogeneous—they have remarkably similar features and properties despite being so far away from each other. The question, therefore, is what caused this apparent homogeneity observed in the universe. If matter rapidly expanded outward, why does the universe have such a uniform appearance in every direction? If the Big Bang theory is correct, some explanation for this horizon problem is needed.
Scientist 1
In the current state of the universe there exist regions that lie beyond the cosmological horizons of others, and therefore cannot possibly be influenced by them. This was not always the case. At a point in time mere microseconds after the Big Bang, all of the matter in the universe experienced a period of exponential expansion, known as inflation, before the rate of expansion fell to a more stable level. This inflation led to all regions of the universe having homogeneous features, even though they are not capable of affecting one another in any way in their current state.
Scientist 2
Although there is ample evidence that a Big Bang occurred, the horizon problem, as well as the flatness problem, suggest that the Big Bang is not the full story of the inception of the universe. The horizon problem can be solved if, instead of viewing the Big Bang as the "beginning of everything," we stipulate that the expansion seen after the Big Bang was already occurring for some time before the Big Bang occurred. This marks the Big Bang as a sort of "causal horizon," which disallows us from directly observing evidence from any period beforehand. If we assume the universe is cyclic, the homogeneity of the universe is explained as the result of a continuous cycle of expansion and compression, which would naturally lead to a universe having uniform features.
Which of the following, if true, would undermine both scientists' positions?
New evidence shows that the Big Bang actually occurred billions of years earlier than formerly thought.
A new study about background microwave radiation has found that the Big Bang must have been the initial event of our universe.
New evidence shows that the oldest galaxies that can be measured from our vantage point are actually receding rather than moving toward us.
New cosmological data suggests that the rate of expansion since the Big Bang has been decelerating at a constant rate.
New evidence suggests that the universe has been slowly expanding outward at a constant rate for an indefinite amount of time.
New evidence suggests that the universe has been slowly expanding outward at a constant rate for an indefinite amount of time.
Both scientists' theories depend on the event of the Big Bang instantiating some set of conditions in the universe. If the Big Bang did not occur, and the universe has been constantly expanding forever, then neither theory would make sense.
The other answer choices are either irrelevant or would only undermine one scientist's argument. Both scientists suggest that older galaxies may be receding due to universal expansion. Scientist 1 argues that the Big Bang was the initial event of the universe; this statement would only weaken Scientist 2's argument. Constant deceleration would deny the inflation period hypothesized by Scientist 1, but support Scientist 2. The exact moment of the Big Bang does not affect either scientist's argument.
Example Question #951 : Act Science
A rover on Mars tests the soil on the planet in Gale Crater. An instrument on the rover dectects steep spikes in methane levels in the soil within 60 days. Additionally, satellite measurements from the area detect unusual plumes of methane from this specific area, which scientists suggest may have once contained an ancient freshwater lake. Two different scientists discuss whether this evidence is conclusive of the existence of life on the planet.
Scientist 1
This is the first evidence that organic life exists on Mars. On Earth, 95% of methane gas is produced by microbial organisms, which points towards the presence of similar biological processes on Mars. The rover has also found evidence of water bound to soil in the crater, and pictures showing carvings in the sides of the crater walls suggest the existence of once-flowing water. Because this water could have supported life in the crater, this methane originated from a bacterial source and shows there is life on the planet.
Scientist 2
There is no evidence of life on Mars. These methane spikes came from organic matter left behind from recent meteor impacts as they degraded in the sun's rays. Although the crater was once filled with water, now all water is bound to minerals in the soil and it not accessible. Methane has also been measured on planets such as Saturn, Uranus, and Neptune, which have conditions too hostile to support life. There is not even enough evidence to suggest that the original water in the crater could have supported life.
Which of the following describes the phenomena to which the scientists attribute methane on Mars?
Scientist 1: Microbial organisms
Scientist 2: Organic matter from meteor impacts degrading in the sun's rays
Scientist 1: Ancient water in the crater
Scientist 2: Microbial organisms
Scientist 1: Organic matter from meteor impacts degrading in the sun's rays
Scientist 2: Microbial organisms
Scientist 1: Microbial organisms
Scientist 2: Ancient water in the crater
Scientist 1: Microbial organisms
Scientist 2: Organic matter from meteor impacts degrading in the sun's rays
Scientist 1 says that the methane comes from microbial organisms, which suggests that life exists on the planet. Scientist 2 says that life does not need to exist on a planet for it to have methane deposits and suggests that it comes from the sun's rays degrading organic matter left from meteor impacts.
Example Question #952 : Act Science
A rover on Mars tests the soil on the planet in Gale Crater. An instrument on the rover dectects steep spikes in methane levels in the soil within 60 days. Additionally, satellite measurements from the area detect unusual plumes of methane from this specific area, which scientists suggest may have once contained an ancient freshwater lake. Two different scientists discuss whether this evidence is conclusive of the existence of life on the planet.
Scientist 1
This is the first evidence that organic life exists on Mars. On Earth, 95% of methane gas is produced by microbial organisms, which points towards the presence of similar biological processes on Mars. The rover has also found evidence of water bound to soil in the crater, and pictures showing carvings in the sides of the crater walls suggest the existence of once-flowing water. Because this water could have supported life in the crater, this methane originated from a bacterial source and shows there is life on the planet.
Scientist 2
There is no evidence of life on Mars. These methane spikes came from organic matter left behind from recent meteor impacts as they degraded in the sun's rays. Although the crater was once filled with water, now all water is bound to minerals in the soil and it not accessible. Methane has also been measured on planets such as Saturn, Uranus, and Neptune, which have conditions too hostile to support life. There is not even enough evidence to suggest that the original water in the crater could have supported life.
According to the information given, upon which of the following points would both scientists agree?
Methane does always point to the existence of life.
Microbial organisms existed on the meteor that created Gale crater.
The water in Gale crater could once have habited life.
There is enough evidence to support the existence of water once on Mars.
There is enough evidence to support the existence of water once on Mars.
Both scientists support the existence of water in the crater in the past. However, Scientist 2 disputes that this could have harbored life and does not agree with Scientist's 1 claim that methane more than likely suggests the existence of biological processes. Neither scientist suggests that organic matter on the meteor came from microbial organisms.
Example Question #953 : Act Science
A rover on Mars tests the soil on the planet in Gale Crater. An instrument on the rover dectects steep spikes in methane levels in the soil within 60 days. Additionally, satellite measurements from the area detect unusual plumes of methane from this specific area, which scientists suggest may have once contained an ancient freshwater lake. Two different scientists discuss whether this evidence is conclusive of the existence of life on the planet.
Scientist 1
This is the first evidence that organic life exists on Mars. On Earth, 95% of methane gas is produced by microbial organisms, which points towards the presence of similar biological processes on Mars. The rover has also found evidence of water bound to soil in the crater, and pictures showing carvings in the sides of the crater walls suggest the existence of once-flowing water. Because this water could have supported life in the crater, this methane originated from a bacterial source and shows there is life on the planet.
Scientist 2
There is no evidence of life on Mars. These methane spikes came from organic matter left behind from recent meteor impacts as they degraded in the sun's rays. Although the crater was once filled with water, now all water is bound to minerals in the soil and it not accessible. Methane has also been measured on planets such as Saturn, Uranus, and Neptune, which have conditions too hostile to support life. There is not even enough evidence to suggest that the original water in the crater could have supported life.
Which of the conditions in Gale crater would Scientist 1 support but Scientist 2 not support?
Water in the Martian soil can still support life.
There is water not bound to the soil.
Gale crater was formed by a meteor impact.
Organic matter from the meteor impact is still present in the soil.
Water in the Martian soil can still support life.
Only Scientist 1 mentions the water in the soil supporting life, while Scientist 2 suggests that it is not accessible. Scientist 1 never mentions there presently being water present apart from the soil or there being organic matter from the meteor in the soil. Both would support the claim that the crater was formed by a meteor.
Example Question #954 : Act Science
A rover on Mars tests the soil on the planet in Gale Crater. An instrument on the rover dectects steep spikes in methane levels in the soil within 60 days. Additionally, satellite measurements from the area detect unusual plumes of methane from this specific area, which scientists suggest may have once contained an ancient freshwater lake. Two different scientists discuss whether this evidence is conclusive of the existence of life on the planet.
Scientist 1
This is the first evidence that organic life exists on Mars. On Earth, 95% of methane gas is produced by microbial organisms, which points towards the presence of similar biological processes on Mars. The rover has also found evidence of water bound to soil in the crater, and pictures showing carvings in the sides of the crater walls suggest the existence of once-flowing water. Because this water could have supported life in the crater, this methane originated from a bacterial source and shows there is life on the planet.
Scientist 2
There is no evidence of life on Mars. These methane spikes came from organic matter left behind from recent meteor impacts as they degraded in the sun's rays. Although the crater was once filled with water, now all water is bound to minerals in the soil and it not accessible. Methane has also been measured on planets such as Saturn, Uranus, and Neptune, which have conditions too hostile to support life. There is not even enough evidence to suggest that the original water in the crater could have supported life.
Which of the following discoveries would support the claims of Scientist 2?
The rover finding remains from the meteor that created Gale crater
Evidence of accessible water
Seismographs on the rover suggesting recent meteor impacts around Gale crater
Recent volcanic activity under the surface of Mars
Seismographs on the rover suggesting recent meteor impacts around Gale crater
Only the seismographs showing recent meteor imapcts would support Scientist 2's theory that the methane came from organic matter from meteors degrading in rays from the sun
Example Question #15 : How To Find Conflicting Viewpoints In Earth And Space Sciences
A rover on Mars tests the soil on the planet in Gale Crater. An instrument on the rover dectects steep spikes in methane levels in the soil within 60 days. Additionally, satellite measurements from the area detect unusual plumes of methane from this specific area, which scientists suggest may have once contained an ancient freshwater lake. Two different scientists discuss whether this evidence is conclusive of the existence of life on the planet.
Scientist 1
This is the first evidence that organic life exists on Mars. On Earth, 95% of methane gas is produced by microbial organisms, which points towards the presence of similar biological processes on Mars. The rover has also found evidence of water bound to soil in the crater, and pictures showing carvings in the sides of the crater walls suggest the existence of once-flowing water. Because this water could have supported life in the crater, this methane originated from a bacterial source and shows there is life on the planet.
Scientist 2
There is no evidence of life on Mars. These methane spikes came from organic matter left behind from recent meteor impacts as they degraded in the sun's rays. Although the crater was once filled with water, now all water is bound to minerals in the soil and it not accessible. Methane has also been measured on planets such as Saturn, Uranus, and Neptune, which have conditions too hostile to support life. There is not even enough evidence to suggest that the original water in the crater could have supported life.
In the paragraph concerning Scientist 1's opinion, he or she uses evidence of water having existed on Mars in the past to support the existence of life on Mars. How does Scientist 2 disagree with this?
The existing water on Mars is bound to the soil.
The water that may have existed on Mars in the past came from remnants of the meteor impact.
The water that may have existed on Mars in the past has not been shown to be suitable for life.
There is no evidence of water ever having existed on Mars.
The water that may have existed on Mars in the past has not been shown to be suitable for life.
Scientist 2 says that water may not have been suitable for life even though it existed. He does not say that this is from the meteor impact. He says that the water is bound to minerals, not the soil itself.
Example Question #21 : How To Find Conflicting Viewpoints In Earth And Space Sciences
A rover on Mars tests the soil on the planet in Gale Crater. An instrument on the rover dectects steep spikes in methane levels in the soil within 60 days. Additionally, satellite measurements from the area detect unusual plumes of methane from this specific area, which scientists suggest may have once contained an ancient freshwater lake. Two different scientists discuss whether this evidence is conclusive of the existence of life on the planet.
Scientist 1
This is the first evidence that organic life exists on Mars. On Earth, 95% of methane gas is produced by microbial organisms, which points towards the presence of similar biological processes on Mars. The rover has also found evidence of water bound to soil in the crater, and pictures showing carvings in the sides of the crater walls suggest the existence of once-flowing water. Because this water could have supported life in the crater, this methane originated from a bacterial source and shows there is life on the planet.
Scientist 2
There is no evidence of life on Mars. These methane spikes came from organic matter left behind from recent meteor impacts as they degraded in the sun's rays. Although the crater was once filled with water, now all water is bound to minerals in the soil and it not accessible. Methane has also been measured on planets such as Saturn, Uranus, and Neptune, which have conditions too hostile to support life. There is not even enough evidence to suggest that the original water in the crater could have supported life.
According to Scientist 1, which of the following must be present if there is life on Mars?
Minerals in the soil
Organic matter from meteor impacts
Methane
Flowing water
Methane
The scientist uses the presence of methane to support the exisetnce of life on Mars. He or she does not acknowledge flowing water to be currently on Mars. The other two choices are mentioned by Scientist 2.
Example Question #952 : Act Science
In describing how layers of earth are formed in a valley in southern Tanzania, two scientists provide separate explanations.
Scientist 1: Over time, sediments accumulate on the ground due to wind or water carrying those sediments to or from the valley. As external conditions change over time, new sediments come in and cover the old layer of sediment, creating a boundary between the older layer and the newer layer. This process continues, creating what we know as the layers of sediment on Earth. These layers remain in place indefinitely due to the weight of new layers being added on top of them.
Scientist 2: Sediments accumulate in the valley due to a variety of weather or climate conditions. As climate changes over time, different types of sediments may be introduced to the valley. Sediments can shift within the ground according to their density when water accumulates within the ground, causing layers to mix, blur, and sometimes switch.
On which of the following statements are the two scientists most likely to agree?
Weather conditions are not important to consider in the formation of sediment layers.
An object found in a lower layer of ground is necessarily older than an object found in a layer closer to the surface.
The process of sediment setting in the valley takes many years.
Sediment density is important in determining the sediment makeup of the valley.
The process of sediment setting in the valley is a process whose length depends on weather conditions.
The process of sediment setting in the valley takes many years.
The correct answer is "The process of sediment setting in the valley takes many years." Both scientists refer to climate changes being important in the sediment makeup of the valley. Climate changes take a very long time, and therefore it is likely that both scientists would agree with the above statement. The other responses are either points that are irrelevant to the passage, or with which only one or neither of the scientists would likely agree according to the information provided.
Example Question #23 : Earth And Space Sciences
In describing how layers of earth are formed in a valley in southern Tanzania, two scientists provide separate explanations.
Scientist 1: Over time, sediments accumulate on the ground due to wind or water carrying those sediments to or from the valley. As external conditions change over time, new sediments come in and cover the old layer of sediment, creating a boundary between the older layer and the newer layer. This process continues, creating what we know as the layers of sediment on Earth. These layers remain in place indefinitely due to the weight of new layers being added on top of them.
Scientist 2: Sediments accumulate in the valley due to a variety of weather or climate conditions. As climate changes over time, different types of sediments may be introduced to the valley. Sediments can shift within the ground according to their density when water accumulates within the ground, causing layers to mix, blur, and sometimes switch.
Which of the following statements would Scientist 1 most likely support while Scientist 2 would not?
The sediment layers formed in this valley have blurred boundaries that do not clearly mark shifts in weather/climate conditions.
The sediment layers formed in this valley have distinct boundaries that mark significant shifts in weather/climate conditions.
A decade of high rainfall followed by a decade of drought would affect the sediment layers in the valley.
Sediment layer formation is a long-term process.
Sediment properties are the most important factor in determining layer composition.
The sediment layers formed in this valley have distinct boundaries that mark significant shifts in weather/climate conditions.
The correct answer is "The sediment layers formed in this valley have distinct boundaries that mark significant shifts in weather/climate conditions." Assuming Scientist 1 is correct, layers that form do not change once new layers are formed on top of them. This would suggest that when changes do occur that affect the sediment composition, this change is defined by a boundary that does not change over time. Scientist 2 would likely disagree with this statement. This is because Scientist 2 makes the claim that sediment shifts around after it has settled into a layer, which would likely blur any boundaries established by previous shifts in sediment composition.
Example Question #21 : Earth And Space Sciences
In describing how layers of earth are formed in a valley in southern Tanzania, two scientists provide separate explanations.
Scientist 1: Over time, sediments accumulate on the ground due to wind or water carrying those sediments to or from the valley. As external conditions change over time, new sediments come in and cover the old layer of sediment, creating a boundary between the older layer and the newer layer. This process continues, creating what we know as the layers of sediment on Earth. These layers remain in place indefinitely due to the weight of new layers being added on top of them.
Scientist 2: Sediments accumulate in the valley due to a variety of weather or climate conditions. As climate changes over time, different types of sediments may be introduced to the valley. Sediments can shift within the ground according to their density when water accumulates within the ground, causing layers to mix, blur, and sometimes switch.
On which of the following points would the two scientists most likely disagree?
The types of sediments found in the valley are affected by climate.
Heavier sediments are usually found lower in a cross section of the ground of this valley.
A cross-section of the ground layers in this valley reveals layers that are chronological in order of youngest nearest the surface to oldest at the greatest depths.
Sediments in this valley are highly varied.
The process of forming sediment layers in this valley takes a very long time.
A cross-section of the ground layers in this valley reveals layers that are chronological in order of youngest nearest the surface to oldest at the greatest depths.
The answer is "A cross-section of the ground layers in this valley reveals layers that are chronological in order of youngest nearest the surface to oldest at the greatest depths." Scientist 1 states that the layers in the valley do not change after they are formed due to the weight of the above layers. This would indicate that a cross-section of the layers of earth in this valley would be chronological—older sediment would be found lower on the cross-section. Scientist 2, however, claims that although the layers may begin chronologically, factors such as the sediment's density can influence the makeup of the ground. This means that Scientist 2 would likely disagree that a cross section would be chronological because, assuming Scientist 2's statement is correct, the layers could switch around over time.
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