To find the total cost \( c \) per month for water services when the monthly usage is 1,200 gallons, we can plug in \( x = 1200 \) into the function \( c = 0.25x + 20 \).
The calculation will be as follows:
\[ c = 0.25(1200) + 20 \]
First, calculate \( 0.25 \times 1200 \):
\[ 0.25 \times 1200 = 300 \]
Next, add the fixed fee of \( 20 \):
\[ c = 300 + 20 = 320 \]
Therefore, when the water usage is 1,200 gallons, the total cost is \( 320 \).
This gives us the point \( (1200, 320) \).
Given the options:
A. \( (1,200, 320) \)
B. \( (1,200, 300) \)
C. \( (1,200, -180) \)
D. \( (320, 1,200) \)
The point that accurately represents a monthly usage of 1,200 gallons is:
A. \( (1,200, 320) \)