[" 30.In a typical Indian Bugghi (a luxury cart drawn by "],[" horses),a wooden plate is fixed on the rear on which "],[" one person can sit.A bugghi of mass "200kg" is moving "],[" at a speed of "10km/h" .As it overtakes a school boy "],[" walking at a speed of "4km/h" ,the boy sits on the wooden "],[" plate.If the mass of the boy is "25kg" ,what will be the "],[" new velocity of the bugghi? "]