A ball A of mass 1 kg moving at a speed of 5 m/s strikes tangentially another ball B initially at rest. The ball A then moves at right angles to its initial direction at a speed of 4 m/s. If the collision is elastic, the mass (in kg) of ball B and its momentum after collision (in kg-m/s) respectively are (approximately)

A

1.2 and 1.8

B

2.2 and 3.3

C

4.6 and 6.4

D

6.2 and 9.1