dollars per hour = salary
a
dollars per hours multiplied with hours worked (h) = total earnings
b
15 x 2 = 30
15 x 3 = 45
15 x 5 = 75
(h)
The axis of symmetry of a quadratic function

is given by the equation

, where h is the x-coordinate of the vertex and is equal to

.
1.

2.

3.

The functions ranked from least to greatest based on their axis of symmetry: h(x), f(x), g(x).
That would be 5x-5 because the number inside is multiplied by the numbers inside due to the brackets. Hope u understand my explanation.
The answer for this question is (a)5
Hope it helps!