The quality assurance department at a gear found that there were 3 defective gears for every 500 produced. Write this as a fraction and as a precent. Please explain

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.