The easiest way to solve this problem is to write out the first few numbers of the sets. 

Set R (multiples of 4): $\displaystyle 4, 8, 12, 16, 20, 24$

Set W (multiples of 8): $\displaystyle 8, 16, 24$

Set X (multiples of 2): $\displaystyle 2, 4, 6, 8, 10, 12$

Set Y (multiples of 6): $\displaystyle 6, 12, 18, 24$

Set Z (multiples of 1): $\displaystyle 1, 2, 3, 4, 5, 6$

Set Q (multiples of 7): $\displaystyle 7, 14, 21, 28$

Given that Set W is the only set in which the entire set of numbers is reflected in Set R, it is the correct answer. 

Determining sequences can take some trial and error, but generally aren't as intimidating as they may at first appear. For this sequence, you multiply the first term by 3, and then subtract 3 two times in a row. Then repeat. When you get to 33, you have only subtracted 3 once, so you have to do that one more time:

$\displaystyle 33-3=30$

In order to find the next number in the sequence, take a look at the patterns and common differences between the existing numbers in the sequence. Starting with $\displaystyle 5$, we add $\displaystyle 4$ to get $\displaystyle 9$, subtract $\displaystyle 3$ to get $\displaystyle 6$, and then repeat. 

When we get to $\displaystyle 9$ for the second time in the sequence, we are adding $\displaystyle 4$ to get $\displaystyle 13$. By the next step in the sequence, we will subtract $\displaystyle 3$ to get the missing number $\displaystyle 10$.

In order to find the next number in the sequence, take a look at the patterns and common differences between the existing numbers in the sequence. Starting with $\displaystyle 1$, we add $\displaystyle 10$ to get $\displaystyle 11$ and then subtract $\displaystyle 5$ to get $\displaystyle 6$.

By the time we get to $\displaystyle 21$, we have subtracted $\displaystyle 5$ from $\displaystyle 26$ to complete the cycle of common differences. We will therefore add $\displaystyle 10$ to $\displaystyle 21$ next, getting the missing number $\displaystyle 31$.

In order to find the next number in the sequence, take a look at the patterns and common differences between the existing numbers in the sequence. Starting at the beginning, we multiply $\displaystyle 2$ by $\displaystyle 4$ to get $\displaystyle 8$ and then divide by $\displaystyle 2$ to get $\displaystyle 4$. 

We multiply the second $\displaystyle 16$ in the sequence by $\displaystyle 4$ to get $\displaystyle 64$, so by the logic of the sequence we will be dividing by $\displaystyle 2$ to get the missing number $\displaystyle 32$.

Subtract the first term from the second term to find the common difference.

$\displaystyle 19-12=7$

Subtract the first term from the second term to find the common difference.

$\displaystyle 25-(-50)=25+50=75$

Subtract the first term from the second term to find the common difference.

$\displaystyle -7-(-12)=-7+12=5$

Subtract the first term from the second term to find the common difference.

$\displaystyle 47-120=-73$

Subtract the first term from the second term to find the common difference.

$\displaystyle 19-8=11$