6.A binomial distributioin is symmetrical if p, the probability of success in a single trial is

7.The probability that a plant will live is 3/4 and the probability that another plant lives is 1/3. the probability that only one of them lives is

8.An experiment can result in only 3 mutually exclusive events A, B and C. If P(A) = 2P(B) = 3P(C), then P(A) =

9.There are four letters and four addressed encelopes. The probability that all letters are not dispatched in the right envelope is

10.The probability that the fifth day of a randomly chosen month of a randomly chosen year will be a Friday, is