Science physics problem solving help!?

Question

A bus travelling 50 m/s is increasing its speed at the rate of 4 m/s, find the distance covered in 6 sec

B) if its speed is decreasing at the rate of 4 m / squared, find the distance covered in 6 secs and the time it takes to come to rest

Answer 1

a) the distance covered is calculated by the formula

    s=ut+1/2at2

    s=50x6+1/2x4x6x6

    s=372

b)similarly, if the speed is decreasing at a rate of 4m/s

   s=ut+1/2at2

     =228

to find the time taken,

  v=u+at

0=50+(-4)t

4t=50

t=12.5s

(where u=initial velocity

             v=final velocity

             a=acceleration

            t=time

             s=distance)