An engineer is setting a speed limit on a road. She wants a car to be able to stop in 66.0ft and knows that the maximum rate at which a car can safely brake is 23.0ft/s^2. Put in terms of mph!

An electron moves with a constant horizontal velocity of 3.0 × 106 m/s and no initial vertical velocity as it enters a deflector inside a tv tube. the electron strikes the screen after traveling 26 cm horizontally and 19 cm vertically upward with no horizontal acceleration. what is the constant vertical acceleration provided by the deflector? (the effects of gravity can be ignored.)