A function $y(t)$ satisfies the differential equation $$\frac{dy}{dt} = y^{4}+6y^{3}-16y^{2}.$$

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1. For what values of $y$ is $y$ increasing?
Answer (in interval notation):

2. For what values of $y$ is $y$ decreasing?
Answer (in interval notation):

3. What are the constant solutions of the equation?
Answer (separate by commas): $y =$

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