1. The seventh-ranked industrial chemical in U.S. production is phosphoric acid, whose chemical formula is H3PO4(M2=97.99g/mol). One method of manufacture starts with elemental phosphorus, which is burned in air and then hydrated (P4m+5S2(w+6H2On4H3PO4m). In 1995, the United States manufactured 2.619104 pounds of phosphoric acid. How many kg of P4(Mc=123.896 g/mol) were needed to manufacture 2.619108 pounds of phosphoric acid, assuming a 100% yield? Calculate the actual \% yield, if 5.113107kg of P4 was needed to manufacture 2.619108 pounds of phosphoric acid. (1lb=453.6g ) (Total 8 points)