3.) If
then this means that Q' is the complement of Q, or in other words, it includes all of the numbers in the universal set that Q does not include. This means that
. The answer is the third option.
4.) Think of the symbol ⊆ as the phrase "a subset of". For this question, this is false. This is because A does not take any numbers from B.
5.) This is true, because U is the universal set, and set B is a subset of U. We can see that it has the numbers 4, 5, and 6.
Hope this helped.