QUESTION 6 Assume that the height of South African adult males has normal distribution, with an average of 166 cm and a standard deviation of 9 cm. (a) What percentage of South African adult males are between 156 cm and 176 cm in height? (4 ) (b) Find the first and third quartiles of the height distribution of South African adult males. (8) (c) A bed manufacturer wants to make a bed long enough to fit at least 99% of South African adult males. What is the height of the tallest person they should accommodate to achieve this? (8) [15) Total marks: [10