The answers are marked in the attached image. The associative property of addition states that we can group numbers in any order we want as long as we're adding them. The same applies for the associative property of multiplication.
A similar rule is the commutative property of multiplication which says we can multiply numbers in any order. Example: 2*3 is the same as 3*2. Addition works this way as well. Example: 5+7 is the same as 7+5