Using Trigonometric Functions to Solve Real-World Scenarios

Suppose the function $y=5tan\left(\frac{\pi }{4}t\right)$ marks the distance in the movement of a light beam from the top of a police car across a wall where $t$ is the time in seconds and $y$ is the distance in feet from a point on the wall directly across from the police car.

ⓐ Find and interpret the stretching factor and period.
ⓑ Graph on the interval $\left[0,5\right].$
ⓒ Evaluate $f\left(1\right)$ and discuss the function’s value at that input.

Its source prints no answer for this problem, so there's nothing to check against.

OpenStax, Algebra and Trigonometry 2e · §8.2 Graphs of the Other Trigonometric Functions · Example 9