What is the average number of cars sold per month at a dealership?
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Question: The graph of a quadratic function opens upward and passes through (1, 4). If the vertex is located at (2, -3), find the equation of this quadratic function.
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Question: Find the extreme value for the function f(x) = (x^3 - 6x^2 + 9x) on the interval [0, 4].