9 ½ hours
The average amount of sleep that teenagers get is between 7 and 7 ¼ hours. However, they need between 9 and 9 ½ hours studies show.
Secondhand smoke contains more than 7,000 chemicals. Hundreds are toxic and about 70 can cause cancer. ... Secondhand smoke causes numerous health problems in infants and children, including more frequent and severe asthma attacks, respiratory infections, ear infections, and sudden infant death syndrome (SIDS).
"Use the settings of the machine to decrease the intensity" is the one among the following choices given in the question that he should o the next time he uses this machine to get the most effective workout. The correct option among all the options that are given in the question is the second option or option "B".
