I really need help I suck at this subject :(

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

The circle below is centered at the point (3, 1) and has a radius of length 2. what is the equation?

Robert has 78 tomatoes and 56 cucumbers he wants to plant them in equal rows how many in each row