Emma is driving her car intially at constant speed toward Julie, who is standing on the road in front of her. Emma tries to warn her and sounds the horn which emits a loud 350.0Hz sound. Julie hears the horn at 380.0Hz. The air temperature is 10.00°C. 

a. How fast is the car moving? 

b. Emma, seeing that Julie is not moving, starts braking when she is 70.00m away. The car is capable of a braking acceleration of -5.30m/s². Does she hit Julie?