How can I find the probability in this problems ?

please explain step by step

27) Among the contestants in a competition are 49 women and 20 men. If 5 winners are randomly selected, what is the probability that they are all men? Round to five decimal places. 27) A) 0.00138 B) 0.01133 C) 0.00813 D) 0.18061 28) A sample of 4 different calculators is randomly selected from a group containing 46 that are 28) defective and 26 that have no defects. What is the probability that all four of the calculators selected are defective? Round to four decimal places. A) 0.1021 B) 0. 1666 C) 0.1586 D) 10.9154 46 0 0 + 12 x 1 + 34 0 2 +2 05 # 3 t. 0 7 x 4 Find the mean of the given probability distribution. 29) 29) x | P(x) 0 0,420 1 0.12 /6.12 1.23 2 0.34 06 3 0.05 0 . 05 4 0.07 0 - 28 A) H = 1.65 B) J = 1.23 C) H = 1.55 D) H = 1.13