)the deering manufacturing company’s short- run average cost function in 2014 was ac = 3 + 4q, where ac is the firm’s average cost (in dollars per pound of the product), and q is its output level.
a. obtain an equation for the firm’s short- run total cost function.
b. does the firm have any fixed costs? explain.
c. if the price of the deering manufacturing company’s product (per pound) is $3, is the firm making profit or loss? explain.
d. derive an equation for the firm’s marginal cost function.

a. the firm short run total cost is =  AC * Q = (3+ 4Q)*Q = 3Q + 4Q²

b. Yes, the firm has a fixed cost

c. Yes.. the firm is making loss

d. MC =Δ(3Q + 4Q²) / ΔQ =

Explanation:

short run is a period of time during which one or more firm input cannot be change.

average cost is the average cost per unit output = TC/Q

from the question, AC = 3+ 4Q

a. the firm short run total cost is =  AC * Q = (3+ 4Q)*Q = 3Q + 4Q²

b. Yes, the firm has a fixed cost

   Fixed cost is the cost of input that remain constant through out the short run. most operating firm has a fixed cost.

   Average cost can be calculated by Average fixed cost + average variable cost. the fixed cost can be assumed to be 3.

c. Yes.. the firm is making loss

Average cost (dollar/pound)=  Total cost/Q

Assume Q is 10.

AC = 3+40 = 43

TC =  3Q + 4Q²= AC*Q = 43*10 = 430

AFC= 3

AVC=40

sale revenue = Q * price = 10 * $3 =$30

AC - Sale revenue = profit or loss

$43 -$30 =  -$13 loss.

d. marginal cost (MC) is the additional cost that results in an increasing output by 1unit.

MC = change in Total Cost divide by change in 1unit quantity increment

MC =Δ(3Q + 4Q²) / ΔQ =

ans.

heterothermic organisms include those organisms that can switch between homeothermic (having body temperature higher than environment) and poikilothermic (having variation in internal body temperature) strategies.

some migratory birds show heterothermy as they decrease their metabolic rate during cold nights to keep their body temperature low. drop in metabolic rate allows increase in production efficiency of birds that reduces the internal body temperature to make it equal to external cold temperature during cold nights.

thus, the correct answer is 'birds allow their temperature drop in order to increase their production efficiency.'