Yes thats a function, it passes the vertical line test!
Answer:
Step-by-step explanation:

2/3
4/6
6/9
8/12
i hope this helps..
I think a scale factor greater than 1
Area of a rectangle is L * W
A = 12 * 18 = 216 ft^2
area of a triangle is : (h * b) / 2......minus the area of the window L * W
A = (10 * 12) / 2 - (4 * 3) = 120/2 - 12 = 60 - 12 = 48 ft^2
216 + 48 = 264 ft^2 <==
and if a gallon covers 70 sq ft......264/70 = 3.77 gallons..rounds to 4 gallons
so ur answer is : A