$3-72.$M Figure P$3-72$ shows a load being applied to an inner cylindrical member that is initially $0\mathrm{.}12$ mm longer than a second concentric hollow pipe. What would be the stress in both members if a total load of $350$ kN is applied?

FIGURE P$3-72$ Aluminum bar in a steel pipe under an axial compression load for Problem $3-72.$

$3-18$ The inner and outer surfaces of a $0\mathrm{.}5-$cm$-$thick $2m2m$ window

glass in winter are $10C$ and $3C,$ respectively. If the thermal conductivity

of the glass is $0\mathrm{.}78\frac{W}{m*C},$ determine the amount of heat loss, in kJ $,$

through the glass over a period of $5$ h $.$ What would your answer be if the

glass were $1$ cm thick?