An engineer is designing a mirror for an optical system. A piece of metal that measures 1.3 cm by 0.83 cm will have a coating of rhodium plated on its surface to serve as the mirror. The rhodium thickness will be 0.00030 mm, and the electrolyte contains Rh³⁺ ions. If the operating current of the electrolysis is 0.10 A, how long must it be operated to obtain the desired coating? What mass of rhodium is deposited? (The density of rhodium is 12.4 g cm^–3.)