Answer: 12
Step-by-step explanation:

Solve for c

Answer:
so basacilly the answer to all of the question is a
Step-by-step explanation: you welcome!
77/5=99/x
77x=5*99
77x=495
x=495/77
x=6.4
she needs to study 6.4 hrs to get 99
I might be wrong but don’t you need two equations to do the elimination process?