I'm a month behind in geometry after being absent this long. ?

Anormally distributed data set has a mean of 176.3 and a standard deviation of 4.2. what is the approximate z-score for the data value of 167.9? 2.00 −2.00 8.4 −8.4

What value is a discontinuity of x squared plus 8 x plus 4, all over x squared minus x minus 6?

The sum of the speeds of two trains is 720.2 mph. if the speed of the first train is 7.8 mph faster than the second train, find the speeds of each.