She wrote a 4 instead of a 3.
There are only 3 numbers that are greater than 7. They are 8, 9, and 10. Mariah must have include 7 in her list. That is how she got 4 instead of 3.
Correct answer is C.
Line

intersects y-axis at -2 and passes through the point (3,-1).
Line must be dashed, because the inequality sign is ">".
Point (0,0) must lie in the solution set because it satisfies inequality

.
My guess would be less than $25