A car with a vertical wind shield moves along in a rain strom at speed of 40 km/hr. The rain drops fall vertically with a terminal speed of 20 m/sec. The angle at which the rain drops strike the wind shield is-
(A) tan-1(5/9)
(B) tan-1(9/5)
(C) tan-1(3/2)
(D) tan-1(2/3)
