The density of copper is 9.86

Eric drew a scale drawing of a country park. the scale he used was 1 inch = 2.5 yards. the picnic area is 80 yards wide in real life. how wide is the picnic area in the drawing ?

Amerchant has coffee worth $60 a pound that she wishes to mix with 50 pounds of coffee worth $90 a pound to get a mixture that she will sell for $70 a pound. how many pounds of the & 60 coffee should be used?

What is the name used to describe a graph where for some value of x, there exists 2 or more different values of y?