The collision of two balls of equal mass takes place at the origin of coordinates. Before collision, the components of velocities are (`v_(x) = 50cm^(-1)` , `v_(y) = 0`) and `(v_(x) = -40cm^(-1)` and `v_(y) = 30cms^(-1)`. The first ball comes to rest after collision. The velocity (components `v_(x)` and `v_(y)` respectively) of the second ball are
A. `10 and 30 cms^(-)`
B. `30 and 10cms^(-1)`
C. `5 and 15cms^(-1)`
D. `15 and 5cms^(-1)`
