Assuming a Constant FIO₂ and Carbon Dioxide Production, Which of the Following

Assuming a constant FIO₂ and carbon dioxide production, which of the following statements are correct?

A) An increased PACO₂ will result in and increased PAO₂.
B) Increased FIO₂ blows off carbon dioxide
C) Increases in $\dot { V }$ _A decrease the PACO₂ and increase the PAO₂.
D) The PAO₂ varies proportionally with the PACO₂.