The coordinate (0, 6) makes the y-intercept = 6. Only one of these functions has that intercept: f(x) = x + 6. If you plug in each coordinate the outputted y-value matches up, making this the right answer.
If you work backwards, she had 24 before going to the movies. This is 3/5 of what she had originally. Use this to find 1/5 the but dividing 24 by 4 = 8 then multiply by 5 to get back to the original value 8 x 5 = 40
