The regulations on the lift in the East Wing of the Red Centre say that the maximum load is 18 people or 1224 kg. Assume that people's weights have mean 68kg and standard deviation 16kg. (a) Consider the load (i.e. total weight) of 18 people standing in a lift.

i. What is the expected load of these 18 people?

ii. What is the standard deviation of the load of these 18 people?

iii. What is the approximate distribution of the load of these 18 people?

iv. Hence find the probability that 18 people would exceed the maximum load, 1224kg.

(b) What is the probability that 17 people would exceed the maximum load?