What does that x2 mean? 2x? or x^2?
I'm confused, the answers are larger than the trail?
I´m pretty sure that the terms would just be 3, 4, and 5. It depends what kind of problem it is.
Answer:
D)Yes, because the difference in the means in the actual experiment was more than two standard deviations from 0.
Step-by-step explanation:
We will test the hypothesis on the difference between means.
We have a sample 1 with mean M1=18.2 (drug group) and a sample 2 with mean M2=15.9 (no-drug group).
Then, the difference between means is:

If the standard deviation of the differences of the sample means of the two groups was 1.1 days, the t-statistic can be calculated as:

The critical value for a two tailed test with confidence of 95% (level of significance of 0.05) is t=z=1.96, assuming a large sample.
This is approximately 2 standards deviation (z=2).
The test statistict=2.09 is bigger than the critical value and lies in the rejection region, so the effect is significant. The null hypothesis would be rejected: the difference between means is significant.
Answer:
-2(16xy-10y+7)
Step-by-step explanation:
-2(16xy-10y-7)= -2×16xy-2(-10y)-2×7
-2(16xy-10y+7)= -32xy+20y-14