In a U-tube, a liquid is poured to a height $h^{\prime}$ in each arm. When left and right arms of the tube is heated to temperature $T_{1}$ and $T_{2}$ respectively, the height in each arm changes to $h_{1}$ and $h_{2}$ respectively. What is the relation between coefficients of volume expansion of liquid and heights, $h_{1}$ and $h_{2}$ ?
(a) $\gamma=\frac{h_{1}-h_{2}}{T_{1} h_{2}-T_{2} h_{1}}$
(b) $\gamma=\frac{h_{1}+h_{2}}{T_{1} h_{2}-T_{2} h_{1}}$
(c) $\gamma=\frac{h_{1}+h_{2}}{T_{1} h_{2}+T_{2} h_{1}}$
(d) $\gamma=\frac{h_{1}-h_{2}}{T_{1} h_{1}-T_{2} h_{2}}$