A food safety guideline is that the mercury in fish should be below 1 part per million​ (ppm). Listed below are the amounts of mercury​ (ppm) found in tuna sushi sampled at different stores in a major city. Construct a 99​% confidence interval estimate of the mean amount of mercury in the population. Does it appear that there is too much mercury in tuna​ sushi?   0.54   0.83   0.09   0.93   1.36   0.57   0.85      What is the confidence interval estimate of the population mean?

A certain prescription medicine is supposed to contain an average of 250 parts per million (ppm) of a certain chemical. If the concentration is higher than this, the drug may cause harmful side effects; if it is lower, the drug may be ineffective. The manufacturer runs a check to see if the mean concentration in a large shipment conforms to the target level of 250 ppm or not. A simple random sample of 100 portions is tested, and the sample mean concentration is found to be 247 ppm. The sample concentration standard deviation is s = 12 ppm. What are the appropriate null and alternative hypotheses? Group of answer choices H 0:  x̄ = 250 vs. H a:  x̄ < 250 H 0:  x̄ = 250 vs. H a:  x̄ ≠ 250 H 0:  x̄ = 250 vs. H a:  x̄ > 250 H 0: μ = 250 vs. H a:μ < 250 H 0: μ = 250 vs. H a: μ ≠ 250 H 0: μ = 250 vs. H a: μ > 250

Consider a normally distributed population with a mean of 196 and a standard deviation of 20. Find the value from this population that gives the 0.195 percentile. (Please round your answer to one decimal place, e.g. 0.6.)

We want to estimate the mean number of chocolate chips per cookie for a large national brand. How many cookies would have to be sampled to estimate the true mean number of chocolate chips per cookie, within 2 chocolate chips and the 98% confidence? Assume that s=11.2 chocolate chips, from a prior sample