3. It serves as the control for the experiment. If he only checks his pulse rate after exercising th en there is no comparison to show whether th rate has increased, decreased, or remained unchanged.
In the mentioned experiment, the pulse rate prior to performing exercise functions as a control of the experiment. Before doing exercise, the pulse rate would be under normal conditions, that is, without changing any variable, and thus is considered as the control for the experiment.
In order to find a change witnessed in the pulse rate post performing exercise, the pulse rate post-exercise would be compared with the control pulse rate.
A teenager's decision to drink alcohol can be influenced by: early introduction to alcohol. exposure to adult binge drinking or alcohol dependence. access to alcohol from parents and others.
