Unfortunately, arsenic occurs naturally In some ground water. A mean arsenic level of # = 8.0 parts per billion (ppb) is considered safe for agricultural use. A well in Texas is used to water cotton crops. This well is tested on a regular basis for arsenic. A random sample of 41 tests gave a sample mean of x = 6.9 ppb arsenic, with s = 2.8 ppb. Does this Information indicate that the mean level of arsenic in this well is less than 8 ppb? Use a = 0.01. LA USE SALT (a) What is the level of significance? State the null and alternate hypotheses. O Ho: H = 8 ppb; H1: H # 8 ppb O Ho: H = 8 ppb; H,: H > 8 ppb O Ho: H > 8 ppb; H1: H = 8 ppb O Hot H = 8 ppb; Hii M 0.100 O 0.050