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The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?

Astraight water slide is 175 feet above ground and is 200 feet long. what is the angle of depression to the bottom of the slide?

What is the area of a rectangle with vertices (-8,-2), (-3,-2), (-3,-6), and (-8,-6)? units