What's the range of this function graph? Question 3 options:

A)

(–∞,2)

B)

[2,∞)

C)

(–2,∞)

D)

[–2,∞]

This is a very simple but very useful example of dimensional analysis. 
12 hours * 5 dollars / hour means that you can cancel the hours out.
One (hours) is in the numerator.
One (hour) is in the denominator.

The plural singular difference does not matter in mathematics.
12 * 5 dollars = 60 dollars.

60 dollars  <<<<< answer