For brainiest:):):):):):)

Which equation represents a proportional relationship that has a constant of proportionality equal to 1/5

If the sales price of a dvd is $20 and the markup is 34%, what is the cost of the dvd?

The area (a) of a circle with a radius of r is given by the formula and its diameter (d) is given by d=2r. arrange the equations in the correct sequence to rewrite the formula for diameter in terms of the area of the circle.