Options

A trader writes one naked put option contracts with $100$ shares. The option price is $$3,$ the strike price is

$$40$ and the stock price is $$42.$ What is the initial margin?

Please report the number with at most two decimals after the decimal point without the dollar sign $($e$.$g$.,$

$00\mathrm{.}00.$ th at most two digits after the decimal point without the dollar sign $($e$.$g$.,00\mathrm{.}00.$ You do not have to write the dollar in your solution$).$

Can you really explain the steps, because i do not understand this question?