66. At the high level of activity in November, 7,000 machine hours were run and power costs were $12,000. In April, a month of low activity, 2,000 machine hours were run and power costs amounted to $6,000. Using the high-low method, the estimated fixed cost element of power costs is a. $12,000. b. $6,000. 0. $3,600. d. $8,400