Give the Focus, Directrix, and Axis for the Parabola

question 25

Multiple Choice

Give the focus, directrix, and axis for the parabola.
-A domed ceiling is a parabolic surface. For the best lighting on the floor, a light source is to be placed at the focus of the surface. If 10 m down from the top of the dome the ceiling is 19 m wide,
Find the best location for the light source.

• A) 9 m down from the top
• B) 4.6 m down from the top
• C) 2.3 m down from the top
• D) 6.9 m down from the top

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Definitions:

Marginal Costs

The additional cost incurred by producing one more unit of a good or service.

Fixed Costs

Costs that do not change with the level of output or sales, such as rent, salaries, and insurance, remaining constant regardless of business activity levels.

Marginal Product

The increase in output that results from employing one more unit of a particular input, holding all other inputs constant.

Average Total Cost

The total cost of production divided by the quantity of output produced. It includes both fixed and variable costs.