In a set of experiments, a physicist makes multiple independent measurements of an electric field. In total, 1600 measurements are made, and we find that the standard deviation of the measurements is 2 V/m, and the mean is 100.0 V/m. Measured in Volts per metre, what is the width of the 95% confidence interval for the value of the field?

An experiment is conducted to compare the maximum load capacity in tons (the maximum weight that can be tolerated without breaking) for two alloys A and B It is Kknown that the two standard deviations in load capacity are equal at 7 tons each. The experiment is conducted on 50 specimens of each alloy (A and B) and the results are X = 75.8. X = 71.8, and X-X=4. The manufacturers of alloy A are convinced that this evidence shows conclusively that Hug and strongly supports the claim that their alloy is superior. Manufacturers of alloy 8 claim that the experiment could easily have given X-X 4 even if the two population means are equal. Complete parts (a) and (b) below. Click here to view page 1 of the standard normal distribution table. Click here to view page 2 of the standard normal distribution table. (a) Make an argument that manufacturers of alloy B are wrong. Do it by computing P(XA-XB41 PA-HB) P(XA-X > 4) - @

Suppose that the hemoglobin levels among healthy females are normally distributed with a mean of 14.1 gdL. Research shows that exactly 95% of healthy females have a hemogoblin level of 16.1 gdL. What is the standard deviation of the distribution of hemoglobin levels and healthy females. Carry you intermediate computations to atleast four decimal places, and round your answer to at least two decimal places.

Question 4 Use the empirical rule to solve the problem. The amount of Jen's monthly phone bill is normally distributed with a mean of $58 and a standard deviation of $12. What percentage of her phonė bills are between $22 and $94? O 99.99% O 99.7% O 68% O 95% « > A Moving to another question will save this response. 4:42 PM rch 3/25/2021 DII FS PrtScn Home F9 End F10 PgUp PgDn F11 F12 F6 F7 F8 4. 5 6 8. 9. E R T Y U D F G H J K L

For a population with a mean of ? = 80 and a standard deviation of ? = 12, a score of X = 77 corresponds to z = −0.50. True or false?

The level of calcium in the blood of healthy young adults follows a normal distribution with mean u = 10 milligrams per deciliter and standard deviation s = 0.4.  A clinic measures the blood calcium of 100 healthy pregnant young women at their first visit for prenatal care.  The sample mean of these 100 measurements is  X = 9.8.  Is this evidence that the mean calcium level in the population from which these women come is less than 10?  To answer this question, we perform the following hypothesis test: H0: u = 10, Ha: u < 10. What is the test statistic? (use two decimal places in your answer) What is the p-value equal to? At the 10% significance level, do you accept or reject the null hypothesis? Answer ACCEPT or REJECT t the 5% significance level, do you accept or reject the null hypothesis? Answer ACCEPT or REJECT

A standardized test is given to a sixth-grade class. Historically the mean score has been 151 with a standard deviation of 21. The superintendent believes that the standard deviation of performance may have recently decreased. She randomly sampled 23 students and found a mean of 161 with a standard deviation of 18.2898. Is there evidence that the standard deviation has decreased at the α=0.05 level? Step 1 of 5 : State of the hypotheses in terms of the standard deviation. Round the standard deviation to four decimal places when necessary Step 2 of 5 : Determine the critical value(s) of the test statistic. If the test is two-tailed, separate the values with a comma. Round your answer to three decimal places. Step 3 of 5 : Determine the value of the test statistic. Round your answer to three decimal places. Step 4 of 5 : Make the decision. Step 5 of 5 : What is the conclusion?

Solve question 9, Part A, Part B and Part C only.