This one is good. This is the exact rationale that I was talking about. F is positive from zero to seven, so it develops all this positive area, and it's non-negative over the interval, and so we are going to stay positive this entire time for g, which is the area under f and above the x-axis from zero to our whatever x we wanna pick. So I like this choice here. F is neither concave up nor concave down over the interval from, the closed interval from seven to 12. No, that doesn't really help us in saying that g is positive over that interval. So there you go, choice C.