If E and F are mutually exclusive events, which of the following

16. If E and F are mutually exclusive events, which of the following must be true?a) P E F P Eb) P E F P E P F P E Fc) P E P F 1d) E and F are independent.e) None of these.17. Suppose 21% of the urban population is 18 years old or younger. Five residents of thatcity are selected at random; find the probability that at least two of the selected fivepersons are 18 years old or younger. Round your answer to two places.a) 0.22 b) 0.17 c) 0.06 d) 0.11 e) None of these.18. A student takes a 5 question multiple choice quiz with 4 choices for each question. Ifthe student guesses at random on each question, what is the probability that the studentgets exactly 3 questions correct?a) 0.066 b) 0.176 c) 0.022 d) 0.088 e) None of these.19. The number of students per classroom in a mid-size college is a random variable whosedistribution is normal with mean 37 students and standard deviation 4 students. Youintend to visit twenty five classrooms, what is the probability that the average number ofstudents per room will be greater than 38.2 students?a) 0.1568 b) 0.8633 c) 0.1467 d) 0.9332 e) None of these.20. The average number of mosquitos in a stagnant pond is 80 per square meter with astandard deviation of 8. If 36 square meters are chosen at random for a mosquito count,find the probability that the average of those counts is more than 81.3 mosquitos persquare meter. Assume that the variable is normally distributed.a) 0.1267 b) 0.3587 c) 0.0520 d) 0.1587 e) None of these.21. For a normal distribution curve with a mean of 6 and a standard deviation of 6, which ofthe following ranges of the variable will define an area under the curve corresponding toa probability of approximately 34%?a) from 0 to 12d) from 6 to 12b) from –6 to 18e) None of these.c) from 3 to 9Revised Spring 2016