Answer:
59.4
Step-by-step explanation:
Suppose that some value, c, is a point of a local minimum point.
The theorem states that if a function f is differentiable at a point c of local extremum, then f'(c) = 0.
This implies that the function f is continuous over the given interval. So there must be some value h such that f(c + h) - f(c) >= 0, where h is some infinitesimally small quantity.
As h approaches 0 from the negative side, then:
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As h approaches 0 from the positive side, then:
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Thus, f'(c) = 0
2.64 divided by 6 equals 0.44. one ounce costs 44 cents
I would say 80, because without an estimate it'd be 79 and 79x5=395. So 80x5=400, which is the estimate of 395. So 80 is the answer