A Block of Mass M=3 $v _ { \mathrm { i } } = 9.3 \mathrm {~m} / \mathrm { s }$

A block of mass m=3.6 kg, moving on a frictionless surface with a speed $v _ { \mathrm { i } } = 9.3 \mathrm {~m} / \mathrm { s }$
sudden perfectly elastic collision with a stationary block of mass M , as shown in the figure. Just
after the collision, the 3.6-kg block recoils with a speed of $v _ { f } = 2.7 \mathrm {~m} / \mathrm { s }$
other block? What is the speed V of the

A) 10.7 m/s
B) 12.0 m/s
C) 9.3 m/s
D) 6.6 m/s
E) 8.0 m/s