What sum is represented by the following number line? a. 2 3/4 + (-3 1/4) = -1 2/4
b. 2 3/4 + ( -4 1/4) = -1 2/4
c. -1 1/2 +2 3/4 = 4 1/4
d. 3 1/4 + (-4 3/4) = -1 2/4

please help

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