Calculate the mass in grams for each of the following liquids. part a 280 ml of gasoline (d = 0.69 g/ml) express your answer to two significant figures and include the appropriate units. part b 190 ml of ethanol (d = 0.79 g/ml) express your answer to two significant figures and include the appropriate units.

The density is calculated as mass per volume, so if we want to solve for mass, we would multiply density by volume.
For Part A: if we have a density of 0.69 g/mL, and a volume of 280 mL, multiplying these will give a mass of: (0.69 g/mL)(280 mL) = 193.2 g. Rounded to 2 significant figures, this is 190 g gasoline.
For Part B: if we have a density of 0.79 g/mL, and a volume of 190 mL, multiplying these will give a mass of: (0.79 g/mL)(190 mL) = 150.1 g. Rounded to 2 significant figures, this is equal to 150 g ethanol.

B. a graduated substance