Find measure angle SPT

An arc subtends a central angle measuring 7pi/4 radians what fraction of the circumference is this arc?

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?

Which diagram best shows how fraction bars can be used to evaluate 1/2 divided by 1/4?