The distribution of claim size under a certain class of policy is modelled as a normal random variable, and previous years records indicate that the standard deviation is 120. i Calculate the width of a 95% confidence interval for the mean claim size if sample of size 100 is available. [3 marks] ii. Determine the minimum sample size required to ensure that a 95% confidence interval for the mean claim size is of width at most 10. [3 marks] i Comment briefly on the comparison of the confidence intervals in (i) and () with respect to widths and sample sizes used. [2 mark]