It take 0.54 hours to deposit 6.36g of copper
Faraday's Law I
"The mass of the substance formed at each electrode is proportional to the electric current flowing in the electrolysis
W = e.i.t / 96500
[tex]\tt \large {\boxed {\bold {W \: = \: \dfrac {e \times i \: x \: t} {96500}}}}[/tex]
e = equivalent = Ar / valence
i = current, A
t = time, s
W=6.36 g
e = 63.5 : 2 =31.75
i = 10 A
[tex]\tt t=\dfrac{W\times 96500}{e.i}\\\\t=\dfrac{6.36\times 96500}{31.75\times 10 }\\\\t=1933.04~s\approx 0.54~hours[/tex]