PROBLEM 2-19 High-Low and Scattergraph Analysis [L04] Sebolt Wire Company heats copper ingots to very high temperatures by placing the ingots in a large heat coil. The heated ingots are then run through a shaping machine that shapes the soft ingot into wire. Due to the long heat-up time, the coil is never turned off. When an ingot is placed in the coil, the temperature is raised to an even higher level, and then the coil is allowed to drop to the "waiting" temperature between ingots. Management needs to know the variable cost of power Chapter 2 involved in heating an ingot and the fixed cost of power during "waiting" periods. The following data on ingots processed and power costs are available Power Cost $5,500 $4,500 $4,400 $5,000 $6,000 S5,600 $4,000 $3.200 $3,400 $2,400 Number 1 Month of Ingots 2 January 3 February 4 March 110 90 80 100 130 120 70 60 50 40 ri 6 May 7 June 8 July 9 August 10 September 11 October 12 Required 1. Using the high-low method, estimate a cost formula for power cost. Express the formula in the form Y- a + bX