Answer
8.39 g Ag
Work Step by Step
Charge $Q=I\times t= 2.78\,A\times 45.0\times60\,s$
$=7506\,C$
According to the equation
$Ag^{+}+e^{-}\rightarrow Ag$
Charge of 1 mol electrons or 96500 C is required to produce 1 mol Ag or 107.87 g Ag.
$\implies$ mass of silver that could be plated=
$\frac{7506\,C}{96500\,C}\times 107.87\,g=8.39\,g$