Costly Texts. The UCSD bookstore claims that only 10% of the textbooks they carry are over $100. After spending too much money on books, Angelo does not believe their claim. He takes a simple random sample
of 100 textbooks and finds that 15% of them are cost over $100. Does he have statistically significant
evidence that the book store's claim is incorrect? Test at 5% level of significance.
ASSUME all conditions have been met.

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