Two balls of masses 3 kg and 6 kg are moving with velocities of 4 m/sec and 1 m/sec respectively, towards each other along the line of their centers. After impact the 3 kg ball comes to rest. This can happen only if the coefficient of restitution between the balls is
A. $$\frac{2}{3}$$
B. $$\frac{1}{5}$$
C. $$\frac{3}{5}$$
D. $$\frac{1}{3}$$
Answer: Option B

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