DO PROBLEM $5-9$ PLEASE

$5-9.$ The moderator temperature coefficient $[$MTC$]$ in Prob. $5-8$ is characteristic of the PWR at end Of $($core$)$ life $[$EOL$]$ when the soluble boron poison concentration is minimum. At beginning of life $[$BOL$]$ when the concentration is high,

$($:${}_m$:$)=-0\mathrm{.}2{10}^{-4}\frac{}{F}$

a$.$ Explain the mechanism that is responsible for the difference.

b$.$ Calculate the average power coefficient for BOL conditions.