An adult inhales about 6.0×10−4 m3 of fresh air during a breath. Only 20% of fresh air is oxygen. Assume the pressure in the lungs is 1.0×105 Paand the air is at a temperature of 300 K.

How many oxygen molecules are in each breath?

A. 1.4X10^23

B. 2.9X10^21

C. 4.9X10^-4

D. 2.9 X10^25