The table below shows the cube roots of different numbers: Number (x) 8 27 64 125 Cube root (y) 2 3 4 5 Part A: Does the table represent y as a function of x? Justify your answer. (5 points) Part B: The total cost f(x), in dollars, for renting a bike for x hours is shown below: f(x) = 15 + 20x What is the value of f(80), and what does f(80) represent?