Two Billiard Balls Undergo a Glancing Collision

Multiple Choice

Two billiard balls undergo a glancing collision.Before the collision the first ball was travelling east at 2.6 m/s and the second ball was travelling west at 1.2 m/s.If the second ball is deflected by +90 degrees travelling north at 1.47 m/s,what is the speed of the first ball after the collision?

A) 1.39 m/s
B) 1.68 m/s
C) 2.57 m/s
D) 2.03 m/s