Business Management—Insurance Costs: The Dakorn Company determines that the annual cost of...

Business Management—Insurance Costs: The Dakorn Company determines that the annual cost of covering its employees’ vision and dental insurance can be modeled by the function

where x represents the number of employees covered and f(x) represents the annual insurance cost in dollars.

(a) Determine the differential dy for the model.

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(b) Suppose that the company’s CEO has decided to hire four new employees in the Human Resources Department, so that the number of employees increases from 250 to 254. Use the differential to approximate the increase in cost in dental and vision insurance.