# Question 12 of 20 00 10 points accepted characters

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Question 12 of 20 0.0/ 1.0 Points Accepted characters : numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A firm that produces light bulbs claims that their lightbulbs last 1500 hours, on average. You wonder if the average might differ from the 1500 hours that the firm claims. To explore this possibility you take a random sample of n = 25 light bulbs purchased from this firm and record the lifetime (in hours) of each bulb. You then conduct an appopriate test of hypothesis. Some of the information related to the hypothesis test is presented below. Test of H 0 : = 1500 versus H 1 : 1500 Sample mean 1509.5 Std error of mean 4.854 Assuming the life length of this type of lightbulb is normally distributed, if you wish to conduct this test using a .05 level of significance, what are the critical values that you should use? Place the smallest critical value, rounded to 3 decimal places, in the first blank. For example, -1.234 would be a legitimate entry. -2.093 . Place the larger critical value, rounded to 3 decimal places, in the second blank. For example, 1.234 would be a legitimate entry. 2.093
Question 13 of 20 0.0/ 1.0 Points Accepted characters : numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A statistician wishes to test the claim that the standard deviation of the weights of firemen is greater than 25 pounds. To do so, she selected a random sample of 30 firemen and found s = 27.2 pounds. Assuming that the weights of firemen are normally distributed, if the statistician wanted to test her research hypothesis at the .05 level of significance, what is the critical value? Place your answer, rounded to 3 decimal places, in the blank. For example, 23.456 would be a legitimate entry. 22.491