Bluebook试题2 · 第 5 题

Caleb used juice to make popsicles.The function f(x) = -5x ＋30 approximates the volume, in fluid ounces, of juice Caleb had remaining after making x popsicles. Which statement is the best interpretation of the y-intercept of the graph of y = f(x) in the xy-plane in this context?