The annual production of sodium hydroxide in the U.S. in 1994 was 25.83 billion pounds.How many grams of sodium hydroxide were produced in that year?The density of sodium hydroxide is 2.130 g/cm3.How many cubic kilometers were produced?

I know how to get the first part which is easy for 1 pound is equal to 453.59 grams. But for the second part I don't understand how you are suppose to convert 2.130 g/cm^3 to km. Can anyone please help me out on this one. Thank you and have a wonderful day