If you know that with 8 units of output, average fixed cost is $12.50 and average variable cost is $81.25, then the total cost at this output level is: Group of answer choices $97.78 $93.75 $880 $750

The table below shows cost data for WipeOutSki Company, which manufactures skis for beginners. If the company’s fixed costs are $30, what is the marginal cost X? Quantity Variable Cost Fixed Cost Total Cost Average Variable Cost Average Total Cost Marginal Cost 0 0 $30         1 $10 $30         2 $25 $30       X 3 $45 $30         4 $70 $30         5 $100 $30         6 $135 $30         Group of answer choices $15 $55 $5

Please don't use excel and show equations used.

3. Minimize the following total cost function: TC = Q³ – 10Q2 + 48Q + 46.