Answer:
Step 2: Commutative Property
Step 3: Associative Property
Explanation:
According to the Commutative Property of Addition: Two real numbers can be added in either order.
a + b = b + a
Therefore, she used the Commutative Property in Step 2.
In Step 3, she used the Associative Property, in which the grouping of the addends does not change the sum.