A 15-G Bullet Is Shot Vertically into an 2-Kg Block

Multiple Choice

A 15-g bullet is shot vertically into an 2-kg block.The block lifts upward 8.0 mm (see the figure) .The bullet penetrates the block and comes to rest in it in a time interval of 0.0010 s.Assume the force on the bullet is constant during penetration and that air resistance is negligible.The initial kinetic energy of the bullet is closest to

A) 21 J.
B) 14 J.
C) 10 J.
D) 0.0012 J.
E) 0.16 J.