Let $f(x) = 4x^{3}+15x^{2}-18x-3.$ Answer the following questions.

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1. Find the interval(s) on which $f$ is increasing.
Answer (in interval notation):

2. Find the interval(s) on which $f$ is decreasing.
Answer (in interval notation):

3. Find the local maxima of $f.$ List your answers as points in the form $(a,b)$.
Answer (separate by commas):

4. Find the local minima of $f.$ List your answers as points in the form $(a,b)$.
Answer (separate by commas):

5. Find the interval(s) on which $f$ is concave upward.
Answer (in interval notation):

6. Find the interval(s) on which $f$ is concave downward.
Answer (in interval notation):

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