Answer:
a) C(1,000)=288,491.11 $
b) c(1,000)=288.49 $/u
c) dC/dx(1,000)=349.74 $/u
d) x=100 u
e) c=220 $/u
Step-by-step explanation:
(a) Find the total cost at a production level of 1000 units.

(b) Find the average cost at a production level of 1000 units.

(c) Find the marginal cost at a production level of 1000 units.

(d) Find the production level that will minimize the average cost.

(e) What is the minimum average cost?

4/17 = 0.235294118 or 4/17
The x-intercepts are indeed -1 and 1.
The increasing intervals are listed as (-1, 0) u (1, infinity) not because -1 and 1 are not included points of the function, but because the function is not differentiable in those points, so you can't tell whether the function is increasing or decreasing there.
Area of a circle = (3.14) * r^2
d = 7
r = 3.5
a = (3.14) * 3.5^2
a = (3.14) * 12.25
a = 38.47