The promoter of a football game is concerned that it will rain. She has the option of spending $13,750 on insurance that will pay $25,000 if it rains. She estimates that the revenue from the game will be $80,000 if it does not rain and $55,000 if it does rain. What must the chance of rain be if she is ambivalent about this insurance?
(a)55% (b)60% (c)65% (d)70% (e)75%