Math question: What is the value of x in the equation log(base 3)(x+3) = 2?
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What is the variance of a dataset containing the following values: 5, 8, 10, 15, 20?
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Find the length of the major axis of an ellipse with a vertical major axis, when the coordinates of the foci are (0, ±9) and the distance between a focus and a vertex is 15.