the circumference of a circle is a(pi) units, and the area of the circle is b(pi) square units. If a=b, what is the radius of the circle

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For which of the following counts would a binomial probability model not be reasonable? a)the number of people in a classroom born in januaryb) the number of people in a classroom with red hair c) the number of people admitted to a hospital in a day with a particular disease d) the number of heart beats in a one-minute perio.

Use the graph of the sine function y=2sinθ shown below