At the opening of a trading day at a certain stock exchange, the price per share of stock K was $28. If the price per share of stock K was $29 at the closing of the day, what was the percent increase in the price per share of stock K for that day? Choose the correct option.
A) 3.57 % B) 5.9 % C) 11.1 % D) 12.5 % E) 23.6 %

Rationale: "opening = 28 closing = 29 rise in price = 1 so , percent increase = 1 / 28 * 100 = 3.57 answer : a"
Answer: A