For a gas whose $p-v-T$ behavior is described by $Z=1+$ $B p / R T$, where $B$ is a function of temperature, derive expressions for the specific enthalpy, internal energy, and entropy changes, $\left[h\left(p_{2}, T\right)-h\left(p_{1}, T\right)\right],\left[u\left(p_{2}, T\right)-u\left(p_{1}, T\right)\right]$, and $\left[s\left(p_{2}, T\right)-s\left(p_{1}, T\right)\right]$