Answer:
Minimum cost is $12427.85
Explanation:
The unit cost C is given as:
where x is the number of cars made.
To determine the minimum cost, C(x), first we determine the minimum value of the quadratic expression

When a>0, C(x) will attain minimum value at the point determined by
.
Comparing
with the general form of a quadratic expression

a=0.3, b=-66, c=14571
Minimum Value occurs at

Therefore, the Minimum Cost, C(x) occurs at the point x=39.6
Substituting x=39.6 into C(x)
C(39.6)=

The Minimum cost is $12427.85