I was wondering if anyone could help me prep for my upcoming test by helping me with these questions I got of a statistics site:

1. In class B.J and Tony were performing a hypothesis test. Both received the same test stat, but B.J’s result was to reject the null hypothesis while Tony’s result was not to reject it. Which is not a possible explanation for why they had different conclusions:

- B.J performed an upper – tail test while Mike performed a lower-tail test

- B.J was performing a one-tail test and Tony was performing a two tail one

- B.J considered the test stat to be z while Tony considered the test stat to be t

- B.J was testing at the 0.1 significance level while Tony was testing at a .05 level

- B.J computed the p-value of the test statistic while Mike compared the test statistic to the corresponding critical value for the t-table of critical values.

I think that I eliminated 4th one and 2nd one, but I don't know about the rest.

2) muA = the mean ACT writing score

muB = the mean of ACT writing score of students who took the practice test

The 99% confidence for the true mean difference between the two means is (2,5). Which statement is the best interpretation of this confidence interval?

- uB – uA with probability 0.99

- It’s likely that the difference uB – uA will exceed 5

- With probability 0.99, the interval (2,5) contains the true difference uB-uA

- uB is about equal to 5, and uA is about equal to 2

- uB – uA is about equal to 3

For this, I think I narrowed it down to the last choice and the 3rd one. I'm not sure if it's one of those or not

Thanks a lot