1.A researcher would like to study if there a difference in the blood sugar levels of two groups of men. A random sample of 30 men between the ages of 25 and 40 is selected and tested. The average level is 9 with the standard deviation is 6. A second sample of 42 men between the ages of 41 and 56 is selected and tested. The average of this group is 11 with the standard deviation is 8. Assume that both variables are approximately normally distributed.

a.What is the point estimate of the mean differences of the blood sugar levels?(1 mark)

b.Find the 95% confidence interval for the difference of the two means.(3 marks)

c.Based on answer in (a), is there a difference in the blood sugar levels between the two groups at 5% significance level? Justify your answer.(2 marks)