a. Each liter of air has a mass of 1.80 grams. How many liters of air are contained in 2.5 x103 kg of air?
I kg = 1,000 grams
[2.5 x 10^3] x 1,000 =2.5 x 10^6 grams of air.
[2,5 x 10^6] / 1.8 =~ 1,388,889 Liters of air in 2.5 x 10^3 kg.
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