Chapter 13, Problem 57PE

A deep−sea diver should breathe a gas mixture that has the same oxygen partial pressure as at sea level, where dry air contains 20.9% oxygen and has a total pressure of $1.01\times {10}^5{\text{N/m}}^{\text{2}}$. (a) What is me partial pressure of oxygen at sea level? (b) If the diver breathes a gas mixture at a pressure of $2.00\times {10}^6{\text{N/m}}^{\text{2}}$, what percent oxygen should it be to have the same oxygen partial pressure as at sea level?