1. Guglielma is rolling a biased dice, for which the probability of landing on a 5 is $\frac{2}{11}.$ She rolls the dice twenty times and records the number of times that it lands on a 5.  Find the probability that

(i) the dice lands on a ‘5’ four times

(ii) the dice lands on a ‘5’ four times, but the final ‘5’ does not occur on the final roll.