. Suppose it is known that 15% of a large population believe cryptocurrencies should be a widely accepted form of payment by retailers. It is proposed to conduct a survey of these people as part of an effort to encourage retailers to introduce this payment method. (a) Find the probability that, in a pilot survey of 16 people, at least three of them favour cryptocurrencies as a payment method. (b) Using a suitable approximation, find the probability of at least three people in favour in a larger random sample of 50 people. In both parts, explain any assumptions you are making in order to justify the methods of calculation which you use.