Math question: What is the amplitude and period of the function f(x) = cos x? How many x-intercepts does it have?
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What is the probability of getting exactly 4 heads in 8 flips of an unbiased coin?
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What are the characteristics of a circle defined by the equation x^2 + y^2 = r^2? Explain the meaning of each term and how they determine the shape and properties of the circle.