Question

2. Keeping in mind the context of this situation, what is the practical domain and practical range of this function?

Answer 1

Since you are already given with how the graph looks like, and you are given the equation to verify the identity of the function, you can determine the domain and range by either inspection of the graph or substituting values to the function.
By inspection, the domain or the possible values of x is any real number from negative infinity to positive infinity or (-∞, +∞).
Again by inspection, the range or the possible values of y is any positive value or any real number greater than 0 to positive infinity or (0, +∞).