Rachel is a stunt driver, and she's escaping from a building that is about to explode!
The variable d models Rachel's distance from her exit (in meters) t seconds after the cameras began recording
the stunt.
d= -38t + 220
What is Rachel's speed?

(b) suppose that consolidated power decides to use a level of significance of α = .05, and suppose a random sample of 100 temperature readings is obtained. if the sample mean of the 100 temperature readings is x⎯⎯ = 60.990, test h0 versus ha and determine whether the power plant should be shut down and the cooling system repaired. perform the hypothesis test by using a critical value and a p-value. assume σ = 5. (round your z to 2 decimal places and p-value to 4 decimal places.)