A water jet is releasing water at the rate of 1.5kg/s and at a speed of 1m/s is focused normally on a 2kg block moving with a uniform velocity 2m/s.The jet is focused in opposite to the motion of the block the speed of the block after the jet is focused for 10seconds is

A) 4.5m/s B)9.5m/s C )7.5m/s D)5.5m/s