In an experiment to measure the speed of a bullet, the bullet is red into a piece of plasticine suspended from a rigid support by a light thread.

Question

(there is a pendulum and two balls, ball one is completely vertical and the bullet hits this ball,and somehow is called plasticine, the second ball has a height of 24m)

The speed of the bullet on impact with the plasticine is V. As a result of the impact, the bullet embeds itself in the plasticine and the plasticine is displaced vertically through a height of 24 cm. The mass of the bullet is 5.2×10−3kg and the mass of the plasticine is 0. 8 kg.

ignoring the mass of the bullet, calculate the speed of the plasticine immediately after the impact. [2]
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(ii) Deduce that the speed V with which the bullet strikes the plasticine is about
160 m s−1 . [2]
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(iii) Estimate the kinetic energy lost in the impact. [3]
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please hep and thank you!