A hammer of mass `1 kg` having speed of `50 m//s`, hit a iron nail of mass `200 gm`. If specific heat of iron is `0.105 cal//gm^(@)C` and half the energy is converted into heat, the raise in temperature of nail is
A. `7.1^(@)C`
B. `9.2^(@)C`
C. `10.5^(@)C`
D. `12.1^(@)C`
