I would like some assistance with the following confidence interval question

Researchers want to estimate the average age that teenagers begin experimenting with drugs. They take a random sample of 100 students were surveyed and it was found that the average teenager started at 18 years. The standard deviation is known to be 5 years. The lower bound for a 90% confidence interval is Select one: a. 14.394. b. 15.256. c. 15.697. d. 16.600. X Researchers want to estimate the average age that teenagers begin experimenting with drugs. They take a random sample of 100 students were surveyed and it was found that the average teenager started at 18 years. The standard deviation is known to be 5 years. The lower bound for a 95% confidence interval is Select one: a. 14.394. to. 15.256. (1. 16.600. d. 15.697. In the past, the average score on an English test is 83%. A lecturer would like to determine if his students are performing better than those in the past. Using the graph below, if the test statistic is negative, the p-value for this test is represented by LEFT RIGHT Select one: a. the area to the left of A and the area to the right of B b. the area to the right of A c. the area to the left of B d. the area in between A and B e. the area to the right of B f. the area to the left of A