21. An unknown substance from planet X has a
density of 10 g/mL. It occupies a volume of 80
mL. What is the mass of this unknown
substance?
a. 8 g
b. .125 g
c. 80 g
d. 800 g

Which expression is equivalent to (4 +6i)^2? ? -20 + 48i 8 + 12i 16 - 36i 20 + 48i

Two airplanes start at the same place and travel in opposite directions, one at 395 miles per hour and the other at 422 miles per hour. how many hours will it take for the planes to be 2451 miles apart?

Julia bought 7 hats a week later half of all her hats were destroyed in a fire. there are now only 12 hats left with how many did she start