Answer:

Step-by-step explanation:
The formula for a circle of radius r centered at (h, k) is ...
(x -h)^2 +(y -k)^2 = r^2
Both of the given points are on the line y=-1. The distance between them is the difference of their x-coordinates, 2 -(-2) = 4. So, the radius of the circle is 4 and the equation becomes ...
(x -2)^2 +(y -(-1))^2 = 4^2
(x -2)^2 +(y +1)^2 = 16 . . . . . . . . . matches choice A
She spent $7.44 because 3.28 + 1.27 + 0.56 + 2.33 = 7.44
Slope of y=1-2x is -2
Using point intercept form:
y-1=-2(x-3)
y-1=-2x+6
y=-2x+7