Match each set of points with the slope of the line formed by the ordered pairs.
(0,0) and (2,1)
slope = -2
(1.-3) and (-1,-3)
slope = 1/2
(-1,3) and (-1,-3)
no slope
(0.7) and (2,4)
slope = -3/2
(0,-1) and (2,-5)
zero slope

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?