The production line where you work can assemble 5 amplifiers every 30 minutes. at this rate, which correctly calculates the number of hours it takes to assemble 230 amplifiers? a) divide 230 by 30 and then multiply by 5 b) divide 230 by 30 and then multiply by 2 c) divide 230 by 5 and then multiply by 2 d) divide 230 by 5 and then multiply by 0.5