Answer:
Carbon monoxide is a poisonous gas that's released when smokers exhale. Nicotine is the chemical in cigarettes (and things of the like) that causes people to feel high.
Explanation:
Carbon monoxide (CO) releases is one of the deadly chemicals released into a smoker's bloodstream. Many people die from carbon monoxide poisoning. It's also in second-hand smoke. Nicotine can be used for medicinal purposes, but mostly is used as a stimulant drug. It can also cause buildup in the arteries and negatively affect the heart and people's hormones.
I'm not exactly sure what you were looking for but did this help?
Answer:
True
Explanation:
Those are systems in your body
Cross-training is athletic training in sports other than the athlete's usual sport. The goal is improving overall performance. It takes advantage of the particular effectiveness of one training method to negate the shortcomings of another