ASAP PLEASE HELP ILL MARK BRAINIEST IF ANSWERED IN LESS THAN 1HR

After two years, how much has been paid into interest?

Which expression is equivalent to sq-80

Jada has a meal in a restaurant she adds up the prices listed on the menu for everything they ordered and gets a subtotal of $42.00. when the check comes, it says they also need to pay $3.99 in sales tax. what percentage of the subtotal is the sales tax