Pls help i dont need work shown just the answer if yk

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

What are the exclude value of mn+3m

Are the corresponding angles congruent? explain why or why not.