finance question about investment class

You entered a long position on TESLA by buying 5. The initial margin is 57% and the maintenance margin in 25%. you borrowed 3173 from the broker when you opened the position and had 19884 in cash. the yearly interest rate is 9%. What is the price of TESLA that triggers margin call one year after the position open?

The current value of the SPY ETF is 298. You are long in 197. The initial margin is 53% and the maintenance margin is 37%. The amount of debt( the broker loan) in the position is 34.732. Compute the amount of additional cash required to restore the margin to its maintenance level.

David opened a position to buy 130 of Netfix at 458. To open the position. David put 26360 of his cash as equity. Today, the price of NFLX is 400. Assume that the initial margin is 25% and the maintenance margin is 15%. compute the return over equity for David.