Suppose John commenced business on 1 January, 2016. During the year ending 31 December, 2016, he bought a quantity of leather shoes at a uniform cost and sold 5,800 of them at $50 each. An inventory check on 31 December, 2016 established he holds 650 unsold pairs. John’s gross profit for the year was $116,000. How much was the cost of a pair of shoes?

(a) $20.

(b) $30.

(c) $27.

(d) $35.