The number of calories in a hamburger varies directly with the hamburgers weight. If a quarter- pound hamburger has 560 calories how many calories does a half pound have??

Ms. ortiz sells tomatoes wholesale. the function p(x)=-80x^2+320x-10, graphed below, indicates how much profit she makes on a load of tomatoes if she makes on a load of tomatoes if she sells them for 4-x dollars per kilogram. what should ms. ortiz charge per kilogram of tomatoes to make on a load of tomatoes?