State the domain and range then determine if the relation is a function

Asphere has a diameter of 10 in. what is the volume of the sphere?

Asmall business produces and sells balls. the fixed costs are $20 and each ball costs $4.32 to produce. each ball sells for $8.32. write the equations for the total cost, c, and the revenue, r, then use the graphing method to determine how many balls must be sold to break even.

Two variables, x and y, vary inversely, and x=12 when y=4. what is the value of y when x=3?