Fully vested incentive stock options exercisable at $38 per share to obtain 27,000 shares of common stock were outstanding during a period when the average market price of the common stock was $48 and the ending market price was $48. By how many shares will the assumed exercise of these options increase the weighted-average number of shares outstanding when calculating diluted earnings per share?

Please do not copy from Chegg otherwise I have to report the answer. Explain the answer thoroughly by showing each step of the calculation.