A copper ball of mass

A copper ball of mass $100 \mathrm{gm}$ is at a temperature T. It is dropped in a copper calorimeter of mass $100 \mathrm{gm}$, filled with $170 \mathrm{gm}$ of water at room temperature. Subsequently, the temperature of the system is found to be $75^{\circ} \mathrm{C}$. $\mathrm{T}$ is given by:

(Given : room temperature $=30^{\circ} \mathrm{C}$, specific heat of copper $=0.1 \mathrm{cal} / \mathrm{gm}^{\circ} \mathrm{C}$ )