Explanation:
Haddock et al. (1998) stated that social factors are the strongest predictors of tobacco use; for example, having friends who smoke and view smoking as attractive significantly increases one's own risk of smoking.
Yes, that is 100% true that the<span> regular heavy drinkers usually have to drink more and more in order to have the same effect.
The reason is that when they drink regularly, their brain gets used to the alcohol and it doesn't have any effect at that certain amount which they intake. So when they feel that taking that much amount of alcohol does feel them good, they drink more and more and there comes a stage when alcohol doesn't have any effect on them.</span>
<span>Edward Jenner discovered a vaccination against [smallpox] by infecting a boy with [cowpox]. He noticed that milkmaids who got cowpox never got smallpox and developed his theory from there. He is the father of the study of immunity and immunisation.</span>
