Proving triangles are right triangles.

In triangle XYZ, the sides XY, YZ and XZ measure 12 ft, 16 ft and 20 ft respectively. Prove that XYZ is a right triangle. (Pythagorean Theorem and identify right triangles)

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