Use six rectangles to find an estimate of each type for the area under the given graph of $f$ from $x=0$ to $x=12.$

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1. Take the sample points from the left-endpoints.
Answer: $L_6 =$

2. Is your estimate $L_6$ an underestimate or overestimate of the true area? Choose one Underestimate Overestimate

3. Take the sample points from the right-endpoints.
Answer: $R_6 =$

4. Is your estimate $R_6$ an underestimate or overestimate of the true area? Choose one Underestimate Overestimate

5. Take the sample points from the midpoints.
Answer: $M_6 =$

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Note: You can click on the graph to enlarge the image.

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