Al\(^{3+}\) + 3e\(^-\) → Al

3e\(^-\) = 3F

3 F produced 27g of Al

3 x 96,500C produced 27g Al

(18 x t) C will produce 9g Al (Recall that Q = I x t)

By simple proportion,

\(\frac{3 x 96500}{18t}\) = \(\frac{27}{9}\)

t = \(\frac{9 x 3 x 96500}{18 x 27}\)

t = 5,361.11 seconds

Since the option is in minutes, we have to convert 5,361 seconds to minutes by dividing by 60 (60 sec = 1 min)

t = \(\frac{5361}{60}\)

t = 89.35 minutes

The correct answer is option B.