The mass of nickel that plates out is 16.4 g.
The half-reaction for the reduction of nickel is
Ni²⁺ + 2e⁻ → Ni
You must make the conversions
minutes → seconds → coulombs → moles of electrons → moles of Ni → grams of Ni
Remember that 1 A = 1 C/s.
Mass of Ni = 60.0 min ×