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Asource of laser light sends rays ab and ac toward two opposite walls of a hall. the light rays strike the walls at points b and c, as shown below: what is the distance between the walls?

Grading scale 1 has the following weights- (tests- 50% quiz- 25% homework- 15% final exam- 10%). calculate your final average if your performance in the class is as follows-test grades- {88, 84, 90, 75, 70, 81); quiz grades- {88, 67, 90, 90, 45, 99, 76, 98, 100}; homework- 90; final exam- 75

Assume that females have pulse rates that are normally distributed with a mean of mu equals 72.0 beats per minute and a standard deviation of sigma equals 12.5 beats per minute. complete parts (a) through (c) below. a. if 1 adult female is randomly selected, find the probability that her pulse rate is between 65 beats per minute and 79 beats per minute. the probability is? b. if 16 adult females are randomly selected, find the probability that they have pulse rates with a mean between 65 beats per minute and 79 beats per minute. the probability is? c. why can the normal distribution be used in part (b), even though the sample size does not exceed 30?