Answer
63.3 g/mol
Work Step by Step
Charge $Q=It=(0.750\,A)(25.0\times60\,s)=1125\,C$
Copper is deposited according to the equation
$Cu^{2+}+2e^{-}\rightarrow Cu$
from which it is clear that 2F charge is needed to deposit one mole $Cu$.
Or $2\times96500\,C$ is needed to deposit 1 mole.
Then the amount of copper in moles deposited by 1125 C=$\frac{1125\,C}{2\times96500\,C/mol}=0.005829\,mol$
Molar mass of Cu=$\frac{\text{mass in grams}}{\text{number of moles}}=\frac{0.369\,g}{0.005829\,mol}=63.3\,g/mol$
