Answer:
b = oxygen is the correct answer.
hope this answer will help you
Answer:
D. Carbon Dioxide
Explanation:
When you breathe in air, you take in the oxygen and release carbon dioxide.
Answer:
I would say that I disagree
Explanation:
because then we are just allowing people to hurt themselves.
Answer:
Target heart rate is generally expressed as a percentage (usually between 50 percent and 85 percent) of your maximum safe heart rate. The maximum rate is based on your age, as subtracted from 220. So for a 50-year-old, maximum heart rate is 220 minus 50, or 170 beats per minute.
Explanation:
