A solid horizontal surface is covered with a thin layer of oil. A rectangular block of mass m=0.4kg is at rest on this surface. An impulse of  1.0Ns is applied to the block at time  t=0 so that it starts moving along the x-axis with a velocity  vt=v0e−t/τ, where v0  is a constant and  τ=4s. The displacement of the block, in metres, at  t=τ  is Take  e−1=0.37.