A $200-$lb block $W$ is suspended by an aluminum rodAB with an elastic modulus $E=$

$10,600$ksi, a coefficient of thermal expansion $=12\mathrm{.}5\frac{{10}^{-6}}{}F,$ and a cross$-$sectional

area $A=0\mathrm{.}15$ in$.{?}^2.$ There is an initial gap of $0\mathrm{.}08$ in$.$ between the block and the floor.

Please determine the normal stress inside the rod when $($a$)$ there is a temperature

increase of $25F$ and $($b$)$ there is a temperature increase of $60F.($Hint: There will be

deformation due to the block's weight, which will reduce the gap.$)$