What is 3 to the 3rd power

Marcus built a model car that is 4 inches wide. what scale was used to build the car if the actual width of the car is 6 feet? a. 1 in. = 2 ftb. 1 in. = 2.5 ftc. 1 in. = 1.5 ftd. 1 ft = 1.5 in.

Yoku is putting on sunscreen. he uses 2\text{ ml}2 ml to cover 50\text{ cm}^250 cm 2 of his skin. he wants to know how many milliliters of sunscreen (c)(c) he needs to cover 325\text{ cm}^2325 cm 2 of his skin. how many milliliters of sunscreen does yoku need to cover 325 \text{ cm}^2325 cm 2 of his skin?

What are “like terms”? why can we only add like terms?