Current Attempt in Progress

On April $1,2023,$ Petey Ltd$.$ paid $\backslash (\backslash$$ $175\backslash )$ for a call to buy $700$ shares of NorthernTel at a strike price of $\backslash (\backslash$$ $27\backslash )$ per share any time during the next six months. The market price of NorthernTel's shares was $\backslash (\backslash$$ $27\backslash )$ per share on April $1,2023.$ On June $30,2023,$ the market price for NorthernTel's stock was $\backslash (\backslash$$ $38\backslash )$ per share, and the fair value of the option was $\backslash (\backslash$$ $10,000\backslash ).$

$($d$)$

Why is there a gain or loss when the option is exercised?