As chief financial officer at Apocalyptic Fitness Supply, you track costs and revenue for the daily manufacturing process for your company's top-selling product, the SpineCrusherTM unstoppable elliptical trainer. Daily production costs are defined by C(x) = 200x + 24000 ????(????) where x = number of units made. R(x) = 400x defines daily revenue where x = number of units sold. How many SpineCrusherTM unstoppable elliptical trainers must be sold daily for the manufacturing process to break even ?