Atriangle has vertices (-1, 2), (3, 1), and (7, 2). what is the approximate perimeter of the triangle? round your answer to the nearest hundredth. a.16 units b.16.24 units c.16.31 units d.17 units (explain how you did it)

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?