Polygraph lie-detector machines are commonly used in criminal investigations. The device measures nervous excitement, operating on the idea that if a person is telling the truth they will remain calm. The American Polygraph Association claims that polygraphs accurately identify liars 90% of the time. In other words, if a person lied, the test results will be positive 90% of the time. . Although the polygraph test is good at identifying liars, there is a 50% chance that the polygraph test will say a truthful person is lying A police force wants to predict the accuracy of lie-detector tests for 1,000 suspected criminals. Assume that 700 per 1,000 suspected criminals tell the truth during polygraph tests. Lie Truth Row totals Test result: negative Test result: positive Column Totals 1,000 What is the probability of a positive test result (i.e. the test result is positive whether or not that person is telling the truth). If necessary, round to four decimal places. Hint: you'll need to complete the table to answer this question. Question 13 3 pts The length of human pregnancies from conception to birth varies according to a distribution that is approximately normal in days with a mean of 266 days and a standard deviation of 16 days. What is the probability that a pregnancy lasts more than 282 days according to the Empirical Rule? 0.16 O 0.84 0.68 0.95 Question 14 3 pts What is the standard deviation of the normal probability curve shown below? Do not round. .68 0 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20