A simple random sample is drawn from a population denoted A, with population mean MA and population variance 62. To pin ideas down, the population is " mature companies spun out from research at Cambridge University", and the variable is employment in such companies. The following sample statistics were obtained: Sample A Sample 80 size: n Sample 10.7 mean:/ A Sample variance: 6.4 where MA = _ _i=1 X; is the sample mean estimator, and A = _, Et-1 (X; - MA) the sample variance estimator. Making clear any assumptions you make obtain the lower bound for a 95% two-sided confidence interval for HA