Modern commercial airliners are largely made of aluminum, a light and strong metal. But the fact thot aluminum is cheap enough that airplanes can be made out of it is a bit of histarical luck. Before the discovery of the Hall-Heroult process in 1886, aluminum was as fare and expensive as gold, What wauld happen if alrplanes had to be made of steel? The fuselage of the Bpeing 747 , which can carry 400 passengers, is approximately a hollow atuminum cylinder without ends, 70.7m long, 6.5m wide, and 2.5mm thick (seo sketch at right). Sappose this fuselage was made of steel (density 7.57g/cm3 ) instead of alluminum (density 2.70g/cm3 ), and let's say the average passenger has a miass of 841k. We'll niso assume the engines cant ift any greater mass than they already do. Calculate the number of passengers that the Boeing 747 coufd carry if its fusclage was made of steel