What is the minimum number of terms needed to determine the median of a set, given that each term is unique and the terms are in strictly increasing order?
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What is the vertex form of the parabola function y = ax^2 and how does changing the value of 'a' affect the parabola's shape, direction, and symmetry?
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What is the measure of angle AOC in a circle, given that angle ABC is 60° and ADC is a straight line?