A $50.0 \mathrm{g}$ block of copper at $90.0^{\circ} \mathrm{C}$ is placed in a beaker containing $200.0 \mathrm{g}$ of water at $20.0^{\circ} \mathrm{C}$. Calculate the final temperature of the copper and water. (The specific heat capacities of copper and water are $0.38 \mathrm{JK}^{-1} \mathrm{g}^{-1}$ and $4.18 \mathrm{JK}^{-1} \mathrm{g}^{-1},$ respoctively. (Section 13.1)