A department of Delta Company incurred the following costs for the month of June. Variable costs, and the variable portion of mixed costs, are a function of the number of units of activity:

Activity level in units $3,500$

Variable costs $ $6,475$

Fixed costs $28,000$

Mixed costs $26,750$

Total costs $ $61,225$

During July, the activity level was $7,000$ units, and the total costs incurred were $$69,000.$

Required:

Calculate the variable costs, fixed costs, and mixed costs incurred during July.

Use the high$$low method to calculate the cost formula for mixed cost.