Question

ari has recently quit smoking. what benefit can he expect to occur within a few hours of quitting? blood oxygen levels returned to normal risk of heart disease cut in half improved liver health reduced coughing and congestion

Explanation:

When a person quits smoking, within a few hours, carbon - monoxide levels in the blood decrease and oxygen levels start to return to normal. The risk of heart disease reduction occurs over a longer time - frame like a year. Improved liver health is not an immediate effect related to quitting smoking in a few hours. Reduced coughing and congestion may improve over days to weeks.

Answer:

blood oxygen levels returned to normal