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ǁ According to recent typical test data, a Ford Focus travels 0.250 mi in 19.9 s, starting from rest. The same car, when braking from 60.0 mi/h on dry pavement, stops in 146ft. Assume constant acceleration in each part of its motion, but not necessarily the same acceleration when slowing down as when speeding up. (a) Find this car’s acceleration while braking and while speeding up. (b) If its acceleration is constant while speeding up, how fast (in mi/h) will the car be traveling after 0.250 mi of acceleration? (c) How long does it take the car to stop while braking from 60.0 mi/h?
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