What to do if a number has double exponents?

Stefania pours 2 liters of orange juice and 1.5 liters of pineapple juice into a punch bowl. how many liters are in the punch bowl?

Roderick wants to draw a circle for which the numerical value of the circumference is greater than the value of the area. which lengths could he use for the radius? check all that apply

How many times larger is 9 × 10^8 than 3 × 10^-5? a. 3 × 10^13 b. 3 × 10^-40 c. 3 × 10^-13 d. 3 × 10^3