# Quiz 8: Cost Analysis and Estimation

The below answers explains the reason for true or false: (A)The marginal cost cuts average cost at its minimum. The answer is true. The below figure explains the relation between average and marginal cost:  MC Cost AC Quantity (B)The breakeven point is when . If total fixed cost and price are held constant, an increase in average variable cost would decrease the breakeven point. The answer is true. (C) Point cost elasticity is change in cost due to change in output.  1, change in cost is greater than change in output: decreasing returns to scale 1, change in cost is less than change output: increasing returns to scale =1, change in cost is equal to change in output: constant returns to scale When there is decreasing returns to scale, the average cost starts rising which is also called as diseconomies of scale. The answer is true. (D) The average cost increases with increasing output. Therefore larger plants can be operated rather than smaller plants which have already reached its peak efficiency. The answer is true. (E)The degree of operating level is defined as follows: If total fixed cost is equal to zero, then increase or decrease in average variable cost does not change the degree of operating level. The answer is false.
Long run average cost is the envelope of short run average cost curves. The following explains the effect on long run average cost curve. (A) A rise in wage rate: A rise in the wage rate will increase the cost for firms of hiring labors. Therefore, the long run average cost curve will shift upward. The long run cost curve shifts from LRAC to LRAC* showing increase in cost and hence an upward shift. (B) A decline in output: This will increase the cost and reduce the quantity. There would be a leftward movement along the same LRAC. The quantity decreases and the cost increase from Q to Q* and C to C* respectively. (C) An energy saving technical change : This will decrease the cost for firms. Therefore, the long run average cost curve will shift downward. The long run cost curve shifts from LRAC to LRAC* showing decrease in cost and hence a downward shift. (D) A fall in interest rate : A fall in interest rate would make capital available cheaper rates. This will reduce the cost of the firm and hence a downward shift in long run average cost curve. (E) An increase in learning or experience : This will help reduce the firm's operational cost and hence a downward shift in the long run average cost curve as shown in the below diagram. The LRAC shifts from LRAC to LRAC*. 