A researcher wants to test achievement scores for home schooled 4^thgraders.He knows that the population average for achievement scores of students who attend school is 250.He samples 110 home schooled 4^thgraders and finds and achievement level of 272 with a standard deviation of 10.Using a 0.01 significance level, the research finds the following:

H₁:250

z: +/- 2.57

z = 2.20

Based on this information, what would you conclude?

Fail to reject the null hypothesis

Reject the null hypothesis

A research wants to test whether a certain sound will make rats do worse (meaning it takes them more times) on learning a maze.In general, it takes rats 18 times to learn the maze.The researcher tests a sample of 30 rats.For the sample, the average number of times it takes for the rats to learn the maze is 38 with a standard deviation of 6.Using a 0.05 significance level, the researcher finds the following:

H₁:> 18

t: 1.699

t = 18.26

Based on this information, what would you conclude?

Fail to reject the null hypothesis

Reject the null hypothesis

Find the lower bound for a 99% confidence interval for a sample of 130 persons, with a mean of 27, and a standard deviation of 4.

26.31

27.45

25.49

26.10