Which solution is valid within the context of the situation? A. $(90,25)$ B. $(40,64.50)$ C. $(30,80)$

Step 1 ：The question is incomplete. It does not provide a context or a situation to determine which solution is valid. We need more information to proceed with this problem.

Step 2 ：\(\boxed{\text{The question is incomplete. It does not provide a context or a situation to determine which solution is valid. We need more information to proceed with this problem.}}\)