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16 billion gallons of avgas were used in the U.S. between 1970-2008. Let’s also say there is about 2.21 g Pb (grams of lead) per gallon of avgas. 2.1 μg Pb/dL is toxic. If only 1 tenth of 1% of the lead made it into children’s blood, how many children can be affected? A) calculate how many tons Pb would be expected to be put into the air due to that use over that time.