Hi, Please can you kindly provide a full solution to this question with workings please. Thank you

(a) The total fixed overhead costs of a business are $80,000 for a relevant range of activity between 3,000 and 6,000 units. Below the relevant range the total fixed overhead cost is $70,000 and above, $90,000. The only other costs are variable costs of $4 per unit at any level of production. Required: Calculate the difference between the total costs at an activity level of 5,200 with that of 2,600