A recent survey of 70 fresh graduates revealed that it took an average of 8 weeks for them to secure a job position.The standard deviation for these fresh graduates to secure a job was 3.4 weeks.

1. Construct a 92% confidence interval for the population mean.Interpret the confidence interval.(4 marks)

1. How large a sample is needed to find the population mean within 1.5 weeks at 99% confidence interval? (2 marks)

1. It was further known that the population mean is 7 weeks and population standard deviation is 4 weeks.What is the probability that the sample mean will be more than 8 weeks?(3 marks)

1. What is the minimum sample size required if the standard error cannot be more than 0.5? (3 marks)