Historically, cyanide levels in a certain region were 100 mg/kg with standard deviation 80 mg/kg. A random sample of n = 72 soil samples were taken form this region. What is the probability that the...

Question a b,c,and d

Extracted text: Historically, cyanide levels in a certain region were 100 mg/kg with standard deviation 80 mg/kg. A random sample of n = 72 soil samples were taken form this region. What is the probability that the average cyanide content of this sample is less than 84 mg/kg? (a) Verify that the assumptions for this computation are met. 1. Independence Assumption, checked by the Randomization Condition: 2. Sample Size Assumption, checked by the Large Enough Condition: (b) What are the centre and spread of the appropriate Normal distribution. E(x) = SD(x) = (c) Compute the z-score for this probability. (d) Draw a rough normal diagram for this test statistic and compute the probability. (e) Write a sentence interpreting this probability.