Plz help me in these questions..............(FIITJEE Package)

1. Prob of A wining a game is 0.4 while that of B is 0.6 . What is the probability of A wining a best of 7 games?

2. If Ram and Shyam selects two numbers at random with replacements from {1,2,3,4.....n}. If the probability that Shyam selects a number less than one selected by Ram is 63/128 then...

a) n is odd b) n is perfect square

c) n is a perfect 4th power d) None

3. The probability that a 6 digit number selected at random contains at most three digits repeated is............

4. A fair coin is tossed 9 times the probability that at least 5 consecutive heads occurs is............

5.Let A B C be 3 independent events such that P(A)=1/3, P(B)=1/2, P(C)=1/4. Then probability that exactly 2 events occurs out of 3 events is...........

:)