4.43 Cost estimation: High-low method (LO3). Ginsburg and Company provides you with the follow- ing data: Month Supervision Cost Labor Hours Machine Hours January $27, 500 2,400 5, 040 February $27, 500 2, 560 5,300 March $32, 540 3, 360 6, 600 April $30, 000 2, 880 6,500 May $32, 630 3, 300 6, 750 Required: a. Use the high-low method to estimate Ginsburg's monthly fixed supervision cost and the cost per labor hour (i.e., assume Ginsburg uses labor hours as its measure of activity). b. Use the high-low method to estimate Ginsburg's monthly fixed supervision cost and the cost per machine hour (i.e., assume Ginsburg uses machine hours as its measure of activity). c. Which of the two estimates, the answer to question (a) or question (b), is likely to be more represen- tative of actual cost behavior? d. Why might a manager believe that neither equation is a good way to estimate supervision costs