25. A study related to age of people purchasing lottery tickets found that the average age is 50.2 years and standard deviation is 13.40 years, based on a sample of 40 people. Calculate the margin of error at 95% confidence level.

Select one:

A. 4.153

B. 2.119

C. 3.485

D. 0.657

26. A farmer claims that his oranges weigh at least 250g each. A researcher found that in a random sample of 20 oranges taken from a farm, the sample yields an average weight of 220g with a standard deviation of 15g. A t-distribution used to test the farmer's claim. Calculate the test statistics for this problem.

Select one:

A. 2.25

B. 8.944

C. -8.944

D. 0.2

28. Given IQ scores are approximately normally distributed with a mean of 100 and standard deviation of 15, the proportion of people with IQs above 130 is....

Select one:

A. 95%

B. 2.3%

C. 5%

D. 68%