Math homework geometry please help

Tom had a total of $220 and he spent $35 on a basketball ticket . what percent of his money did he have left?

Stephen thublin invests $1,000,000 in a 45-day certificate of deposit with 6.55% interest. what is the total interest income from the investment?

In the polynomial below, what number should replace the question mark to produce a difference of squares? x2 + ? x - 36