A survey of 100 high school students provided this
frequency table on how students get to school:
Grade Drive to school Take the bus Walk
Sophomore 2 | 25 13
Junior
13
20
T2
NI
Senior
25
Find the probability that a randomly selected student
either takes the bus or walks.
P(Take the bus U Walk) =
hartadecor

Ur environment is very sensitive to the amount of ozone in the upper atmosphere. the level of ozone normally found is 4.04.0 parts/million (ppm). a researcher believes that the current ozone level is not at a normal level. the mean of 2525 samples is 4.44.4 ppm with a standard deviation of 0.80.8. assume the population is normally distributed. a level of significance of 0.020.02 will be used. make the decision to reject or fail to reject the null hypothesis. answer tables