The graph shows the number of gallons of water in a bathtub after filling it for a certain number of minutes. Fill in the boxes to make a true statement.

The rate of change of the function is _____ per minute.

The initial value is _____.

Coach Keller is having the last names of his players printed on their shirts. The lettering company charges a flat fee and a charge per letter. The table shows the total costs for 15, 20, 25, and 30 letters. Select the correct values to model the situation with a linear function.

What do the slope and y-intercept of the function represent?

A(3, 3)

D(1, 8)

G(2.5, 7)

X(7, 2)

P(0, 6)

\(\text{N}(4\cfrac{1}{2}, 0)\)