a car starts from rest and travels for 5.0 s with a uniform acceleration of -1.5 m/s^2.the driver then applies brakes, causing a uniform acceleration of -2.1m/s^2 for an interval of 3.0s

A10nc charge sits at a point in space where the magnitude of the electric field is 1500 n/c. what will the magnitude of the field be if the 10 nc charge is replaced by a 20 nc charge? assume the system is big enough to consider the charges as small test charges.