What is the angle formed by a straight line and its perpendicular, and how does it relate to the angle formed by two intersecting lines?
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A car dealership sells 200 cars per month with a 20% chance of selling an electric car. What's the probability that they sell exactly 40 electric cars this month?
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What is the derivative of f(x) = 3x^2 - 5x + 2 with respect to x?