Indicate the Effect the Following Changes Would Have on the Rate

Short Answer

Indicate the effect the following changes would have on the rate of gas transfer using the following answer code.
a.Increases the rate of gas transfer
b.Decreases the rate of gas transfer
c.Has no effect on the rate of gas transfer
-Effect on O₂ exchange in the lungs of replacing part of the nitrogen with helium so that the inspired air consists of 60% N, 19% He, and 21% O₂