a. What is the probability that exactly four telephone lines are busy in a day? b. What is the probability that, at least three telephone lines busy in a day? 0. What is the probability that the number of busy telephone lines in a day is at least two but at most four? d. What is the probability that at least one telephone line is busy in a day? e. What is the expected value and variance? Interpret your answer. * *'* Let Us Enhance In one of the banks in Davao City, the number of tellers [X] are busy with customers at 12:00 noon that varies from day to day. Past records indicate the probability distribution of X below, Number of Tellers (X) Probability P(X] 0 0.095 1 0.265 2 0.285 3 0.205 4 0.150 Answer the following questions: 1. What is the probability that exactly two tellers are busy at 12:00 noon? 2. What is the probability that at least three tellers are busy at 12:00 noon? 3. What is the probability that fewer than the four tellers are busy at 12:00 noon? 4. What is the probability that, at least to two, but fewer than four tellers are busy at 12:00 noon? 5. Solve and interpret the mean and variance of the probability distribution