Answer:
1) a. $15
2) a. $50,000
Explanation:
July: n1 = 4,000; c1 =$110,000
January: n2 = 2,500; c1 =$87,500
1) Using the high/low method, the average variable cost is determine as the difference between the highest and lowest activity costs, divided by the difference between the highest and lowest output:

The average variable cost is $15.
2) The total fixed cost is determined by the highest activity cost (c1), subtracted by the product of the highest output and the variable cost (n1 x VC):

Total fixed cost is $50,000.