A middle-aged college professor from Boston is in the Swiss Alps studying astronomy. He arrived two.

A middle-aged college professor from Boston is in the Swiss
Alps studying astronomy. He arrived two days ago and plans to stay the entire
year. However, he notices that he is short of breath when he walks up steps and
that he tires easily with any physical activity. His symptoms gradually
disappear; after two months, he feels fine. Upon returning to the United
States, he has a complete physical exam and is told that his erythrocyte count
is higher than normal.

(a) Attempt to explain this finding.

 (b) Will his RBC count remain at this higher-than-normal
level? Why or why not?