1 . The average height of a random sample of 400 people from a city is 1.75 m. It is known that the heights of the population are random variables that follow a normal distribution with a variance of 0.16. a) Find the value of : i. x= (1 Mark) ii. n = (1 Mark) iii. o = (1 Mark) iv. Of =_ (2 Marks) b) Construct the 95% confidence interval for the average heights of the population. (10 Marks) C) With a confidence level of 90%, calculate the minimum sample size in order for the true mean of the heights to be less than 2 cm from the sample mean? (10 Marks) [Total: 25 Marks]