I place my 0.13kg coffee cup on the roof of my car as I load my daughters for a trip to the grocery store, I then need to run back into house for various forgotten items (diaper bag, coupons, and baby dolls). When I get back to the car, I get the girls settled and start for the store forgetting about my coffee. If the coefficient of static friction between the coffee cup and the roof of the car is 0.24, what is the maximum acceleration the car can have without causing the cup to slide. Ignore air resistance. Additionally, how long should I take to accelerate the car from rest to 45mph (20m/s).

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