Calculate the areas and densities. Report the answers in the correct units. A. the area of a rectangle with sides measuring 3 times 10^1 cm and 3 times 10^-2 cm

B. the area of a rectangle with sides measuring 1 times 10^3 cm and 5 times 10^-1 cm

C. the density of a substance having a mass of 9 times 10^5 g and a volume of 3 times 10^-1 cm^3

D. the density of a substance having a mass of 4 times the 10^-3 g and a volume of 2 times 10^-2 cm^3