1. Suppose the mean heights all sixth-grade students follow Normal distribution with mean( u ) 50 inches and standard deviation 3(o ) inches. a) Find the probability to get an individual exceeds 56 inches8 b) Find the range of individual values to be in the middle 90% area. Which c) Suppose you take a sample of 250( n ) students. Suppose the sampling distribution of sample means follow normal distribution, center (same as population mean u and standard-deviation( --). Then, i) Find the probability that a sample mean is below 52.5 inches. j) Find the range of sample means to be in the middle 95% area