The table shows the marginal cost for a company's product at various production levels.

$($a$)$ Estimate the cost $($not including fixed costs$)$ to produce the first $12,000$ units by considering batches of $2000$ units. Use the initial marginal cost for each batch in your calculations.

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$($b$)$ Use batches of $1000$ units and the ending marginal cost for Consider the graph.

$x$

Is your estimate higher or lower than the actual area?

Is your estimate higher or lower than the actual area?

$($c$)$ Find a new estimate $($using right endpoints$)$ with eight rectangles. A sketch of the rectangles is given.each batch to estimate the cost of raising the production level from $4000$ to $11,000$ units.

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