Karen Manufacturing Company collected the following production data for the past month:

Units Produced Total Cost (Sh)

1,600 44,000

1,300 38,000

1,500 45,000

1,100 33,000

If the high-low method is used, what is the monthly total cost equation?

a. Total cost = Sh 8,800 + Sh 22/unit

b. Total cost = Sh 11,000 + Sh 20/unit

c. Total cost = Sh 0 + Sh 30/unit

d. Total cost = Sh 6,600 + Sh 24/unit