1) Probability that a person will develop immunity after vaccinations is 0.8 .If 8 people are given the vaccine, then probability that all develop immunity is = A) $(0.2)^{8}$ B) $(0.8)^{8}$ C) 1 D) $^{8}C_{6}(0.2)^{6}(0.8)^{2}$ Answer: Option BExplanation: Given probability that a person will develop immunity after vaccination=0.8 $\therefore$ probability of 8 persons that will develop immunity = $(0.8)^{8}$