Algebra help please

Hi will someone please help me with a couple of questions?

Mac deposited $918.78 in a savings account that earns 2.1% simple interest. What is Mac’s account balance after ten years?$1,111.72
$192.94$1,929.44
$938.07 2. Leo deposited$2,476.96 in a savings account that earns 2.9% simple interest. What will Leo’s account balance be in 11 months?
$2,548.79$2,476.96
$2,542.81$3,267.11

3. Macy currently has a balance of $3,418.82 in an account earning simple interest. Eighteen years ago she opened the account with an initial deposit of$2,481. What is the interest rate on the account?
7.7%
1.5%
5.6%
2.1%

thanks so much you are my life saver