Electrochemistry: describe question

A student determines a value for the Avogadro constant using an electrolytic method. Two silver electrodes are placed in an aqueous solution of silver nitrate, $\ce{AgNO3}$. A steady current is passed through the cell for a known time, and the increase in mass of the cathode is measured. The charge on one electron, $e$, is $1.60 \times 10^{-19}\,\text{C}$, and the relative atomic mass of silver is 108.

Describe how the student uses this apparatus to determine a value for the Avogadro constant. In your answer, include the measurements the student must take and how the value of the Avogadro constant is calculated from these measurements.