M5-7 (Algo) Estimating Cost Behavior [LO 5-2, 5-3] Castle Inc. has the following information: Month Amount Units Cost A January $ 80,000 February $112,000 64,000 128,000 Month Amount Units Cost B January $40,000 40,000 February $40,000 80,000 Month Amount Units Cost C January $ 80,000 160,000 February $160,000 320,000 Indicate whether these costs are variable, fixed, or mixed. Cost A Cost B Cost C