fifteen million
One hundred fifty million.
5400 x 150000000 = 810000000000
150000000 x 50000 = 7500000000000
4666.6667
150000000 x 1000000 = 150,000,000,000,000
50000000 km is a looooooong way. You may think it's a long way to the shops but that is nothing compared to Space... 150000000 km is the approximate mean distance from the earth to the sun - the earth follows an elliptical orbit.
780,000,000
1,500,000
alveoli
5400
150,000,000,000 meters.