Physics math problem, please help I'm really confused
At 5:30 pm, Stacey was driving her car at a speed of 25 mph on a straight avenue. Suddenly she notices that she had forgotten to bring her purse, so she immediately makes a U-turn and heads back to her house. Now she looks at her watch, which says 6:00 pm. If her current speed is 40 mph, what is the magnitude of her average acceleration from 5:30 to 6:00 pm in miles per hours squared?
A) 65
B) 15
C) 130
D) 140
