8. At an activity level of 6,900 units in a month, Zelinski Corporation's total variable maintenance and repair cost is $408,756 and its total fixed maintenance and repair cost is $230,253. What would be the total maintenance and repair cost, both fixed and variable, at an activity level of 7.100 units in a month? Assume that this level of activity is within the relevant range. 9. What is the variable cost per unit at the 7100 units per month activity level? 10. What is the fixed cost per unit at the 7100 units per month activity level