1- Online News,In a Harris poll of 2036 adults,40% said that they prefer to get news online.Construct 95% confidence interval estimate of the percentage of all adults who say that they prefer to get their news online. Can we safely say that fewer than 50 % of adults prefer to get their news online?

2- Earthquake Magnitudes -Listed below are the Richter scale magnitude of randomly selected earthquakes.

A-Identify the best poin estimate of the population mean .

B-Construct a 95% confidence interval estimate of the mean magnitude of the population of earthquakes.

C-Write a statement that interprets the confidence interval

3.09 2.76 2.65 3.44 3.01 2.94 3.45 2.72 2.69 2.89 2.71 2.76

3- Lefties- There have been several studies conducted in an attempt to identify ways in which left-handed people are different from those who are right-handed. Assume that you want to estimate the mean IQ of all left-handed adults. How many random left-handed adults must be tested in order to be 99% confident that the mean IQ of the sample group is within four IQ points of the mean IQ of all left-handed adults?Assume that 0 is known to be 15.

4- Bone density test- a bone mineral density test is used to identify a bone disease.The result of a bone density test is commonly measured as a Z score, and the population of Z score is normally distributed with a mean of 0 and a standard deviation of 1.

A- For a randomly selected subject,find the probability of a bone density test score than 1.54.

B-For a randomly selected subject, find the probability of a bone density test score greater than -1.54

C- For a randomly selected subject, find the probability of a bone density test score between -1.33 and 2.33.