The 95% Confidence Interval for an unknown population mean is calculated using a sample size of 64 and is presented as (273, 663). Determine the sample mean and the population standard deviation. [5 marks]

ii.Two students, A and B, from different countries take a similar, though not identical, psychometric test. The test also has a different marking scheme. Below are the student marks, country mean and country standard deviation of marks. Which student did best in their country and why? Explain your answer. [5 marks]