The question asks to convert 3.5 quarts of soup to cups, using 1 quart = 2 pints and 1 pint = 2 cups. Set up the conversion by multiplying 3.5 qt by 2 pt/qt and then by 2 cups/pt to reach the desired unit. In dimensional analysis: 3.5 qt × (2 pt / 1 qt) × (2 cups / 1 pt) shows quarts and pints canceling, leaving cups. Compute 3.5 × 2 = 7, then 7 × 2 = 14 cups, or directly 3.5 × 4 = 14 cups, with units tracking throughout. A frequent error is using only one conversion factor, like just quarts to pints, resulting in 7 cups as in A. Another mistake might be reversing the factors, leading to fractions like D. As a strategy, list all steps with units to catch if intermediate conversions are missed.

The question asks to convert 3.6 kilometers to meters, using 1 kilometer = 1000 meters. Set up the conversion by multiplying 3.6 km by 1000 m/km. Dimensional analysis: 3.6 km × (1000 m / 1 km) cancels kilometers, leaving meters. The calculation: 3.6 × 1000 = 3,600 m, tracking units. Errors often involve decimal placement, like forgetting to move it for A or adding zeros for C. Dividing instead gives D. Strategy: Recall 'kilo' means 1,000, so shift decimal three places right.

We need to convert 2 hours 18 minutes to seconds. First, convert everything to minutes: 2 hr × 60 min/hr = 120 min, plus 18 min = 138 min total. Then convert minutes to seconds: 138 min × 60 s/min = 8,280 s. Alternatively, convert hours to seconds (2 × 3600 = 7,200 s) and minutes to seconds (18 × 60 = 1,080 s), then add: 7,200 + 1,080 = 8,280 s. A common error is forgetting to convert one component or adding 2 + 18 = 20 before converting. Always convert mixed units systematically.

We need to convert 2,750 milliliters to liters. Using the conversion factor 1000 mL = 1 L, we divide: 2,750 mL ÷ 1000 = 2.75 L. Alternatively, set up as: 2,750 mL × (1 L/1000 mL) = 2.75 L. The milliliter units cancel, leaving liters. A common error is multiplying instead of dividing, which would give 2,750,000 L. Another error is misplacing the decimal point, giving 0.275 L or 27.5 L. Remember: when converting to a larger unit (mL to L), the numerical value decreases.

The question asks to convert 0.75 liters of solution to milliliters, using 1 liter = 1000 milliliters. Set up the conversion by multiplying 0.75 L by the factor 1000 mL/L to change to the smaller unit. Dimensional analysis: 0.75 L × (1000 mL / 1 L) cancels liters, leaving milliliters. The calculation is straightforward: 0.75 × 1000 = 750 mL, emphasizing unit cancellation. Common errors include misplaced decimals, such as dividing instead of multiplying to get 0.75 mL or B. Another mistake is using 100 instead of 1000, yielding A. For tests, verify by thinking of known equivalents, like 1 L = 1000 mL, so 0.75 should be three-quarters of that.

We need to convert 3.5 gallons to cups. The conversion path is gallons → quarts → cups. First, convert gallons to quarts: 3.5 gal × (4 qt/1 gal) = 14 qt. Then convert quarts to cups: 14 qt × (4 cups/1 qt) = 56 cups. The key is to multiply by both conversion factors sequentially: 3.5 × 4 × 4 = 56. A common error would be to only use one conversion factor, giving 14 cups (choice A). When converting through multiple units, track each step carefully to avoid missing a conversion.

We need to find the area of a poster measuring 0.9 m by 40 cm in square centimeters. First, convert all measurements to centimeters: 0.9 m = 0.9 × 100 = 90 cm. Now calculate the area: 90 cm × 40 cm = 3,600 cm². The key insight is to convert all linear measurements to the same unit before calculating area. A common error would be to convert 0.9 m² to cm² (which would involve squaring the conversion factor), but here we have linear dimensions that we multiply. Always convert linear measurements first, then calculate area.

We need to convert 7.5 miles per hour to feet per second. Set up the conversion with both distance and time units: 7.5 mi/hr × (5280 ft/1 mi) × (1 hr/3600 s). Calculate step by step: 7.5 × 5280 = 39,600 ft/hr, then 39,600 ÷ 3600 = 11 ft/s. The key is recognizing that we multiply by the distance conversion but divide by the time conversion (or multiply by its reciprocal). A common error is multiplying by both 5280 and 3600, giving 39,600 ft/s (choice C). For rate conversions, always verify your units cancel correctly.

We need to convert 1.8 tons to pounds. The conversion is straightforward: multiply tons by the conversion factor. Set up: 1.8 tons × (2000 lb/1 ton) = 3,600 lb. Notice how the ton units cancel, leaving pounds. A common error would be dividing instead of multiplying, which would give 0.0009 lb. Another error might be misplacing the decimal, giving 360 lb or 36,000 lb. Always check that your answer makes sense: since 1 ton = 2000 lb, 1.8 tons should be slightly less than 2 × 2000 = 4000 lb.

We need to convert 3 pounds 8 ounces to total ounces. First, convert the pounds to ounces: 3 lb × 16 oz/lb = 48 oz. Then add the additional 8 ounces: 48 oz + 8 oz = 56 oz. The key is recognizing this is a mixed-unit measurement where we need to convert and add. A common error would be to multiply 3.8 × 16, treating it as 3.8 pounds, which would give 60.8 oz. Another error is forgetting to add the 8 oz, giving just 48 oz. When dealing with mixed units, convert the larger unit first, then add the smaller unit.