The drugs used by weight conscious peoples to reduce appetite and increase alertness are

Given effects due to ........

- Cancer of lung

- Bronchitis

- Gastric ulcer

- Emphysema

Sleep is prevented by

Withdrawal symptoms of alcohol are

When a man inhales air containing normal concentration of ${O_2}$ as well as $CO$ he suffers from suffocation because

Do you think that friends can influence one to take alcohol/drugs? If yes, how may one protect himself/herself from such an influence?