Question 1: Associative Property of Addition (It does not matter where the parentheses are if it is completely addition.)
Question 2: Identity Property of Multiplication (Multiply anything by 0 to get 0.)
Question 3: Associative Property of Multiplication (It does not matter where the parentheses are as long as there is at least one pair of parentheses and the expression is completely multiplication.)
Question 4: Identity Property of Addition (Add 0 to anything and it stays the same.)