A car speeds up uniformly from rest so that it has a velocity of 30 ms-1 after 20 second. How far does the car travel in first 10 second?

V = Vo + a*t = 30 m/s

0 + a*20 = 30
a = 1.5 m/s^2

d = 0.5a*t^2 = 0.5*1.5*10^2 = 75 m.