Acceleration a=3m/s^2 time t= 4.1seconds Final velocity V= 55km/h initial velocity U= ? First convert V to m/s 36km/h=10m/s 55km/h= 55*10/36=15.28m/s Using the formula V= U+at U= V-at U= 15.28-3*4.1=15.28-12.3=2.98m/s Initial velocity U= 2.98m/s or 10.73km/h (Using the conversion rate 36km/h=10m/s)