A particle is moving along a horizontal straight line. The graph of the position function (the distance to the right of a fixed point as a function of time) is shown below. Answer the following questions only on the interval $(0,8)$.

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1. When is the particle moving toward the right?
Answer (in interval notation):

2. When is the particle moving toward the left?
Answer (in interval notation):

3. When does the particle have positive acceleration?
Answer (in interval notation):

4. When does the particle have negative acceleration?
Answer (in interval notation):

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

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