7. The path traveled by a freely falling body is expressed by the formula $s=\frac{g t^{2}}{2}$, where $g-$ is the acceleration of a freely falling body, a constant for a given latitude. Indicate the independent and dependent variables.
Solution. By assigning different values to time $t$, we can determine the path $s$ for any given time interval $t$. Thus, here $t$ is the independent variable, and $s$ is the dependent variable on $t$.