Show all your work in the space provide. 11. a password is to consist of three letters selected from the set (a, b, c, d, f), followed by three numbers selected from the set (1,2,3,4,5). the numbers (n) and letters (l) may not be repeated. find the total number of possible passwords of the from lll-nnn. ans 12, calculate! -i+1fn-204 and rn # 41. ans 13. if two fair six-sided dice are rolled once, what is the probability of rolling a three and a four? ans 14. suppose a, b and c are events in a sample space s with isl = 120 . also, suppose that iai = 16, bi-8, and ia n bl = 4. what is p(a u b)? ans 15. there are ten defective chips in a batch of 500 chips. if two are sampled at random (his means without replacement) what is the probability that both are defective.