Answer:
b. 
Step-by-step explanation:
Here we are given
and are asked to simplify it. We are going to apply the law of exponents which says that

Hence applying this rule in our problem we get, where a=y and n=3

Hence our C) Option is correct
Answer:
a=2
Step-by-step explanation:
-15a-19-35=-84
-15a-19=-49
-15a=-30
a=2
X= 4 and Y =-5 im not really 100% sure but its all i know
The full answer would be 83.454 but you can just say 83 pounds. Both are right