the number of cells in a tumor doubles every 4.5 months if the tumor begins with one single cell how many cells will there be after 6 years​

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.