1.Serotonin is a substance found in the blood and its concentration may or may not be impacted by the hallucinogenic drug LSD. An experiment was set up to establish whether there might be a relationship between the LSD use and serotonin levels. Twenty-six rats were given a daily dose of LSD, while a control group of 25 rats were simply given a daily dose of water (placebo). After 30 days, serotonin levels were measured in the brains of all the rats.

Results: The control group had an estimated average serotonin concentration of 284 micrograms/g with a sample standard deviation of 30 micrograms/g; whereas the LSD group had an estimated average of 320 micrograms/g with a sample standard deviation of 52 micrograms/g. Assume that the true population variances of serotonin concentrations under the two conditions are equal. Use the appropriate test to determine whether the true mean serotonin concentrations are significantly different at 0.01 significance level.

Name of hypothesis test:

H₀:

H_A:

What is the Test Statistic:

Find (or draw) the Rejection region.

Find the P-value (approximately from the appropriate Table or exactly using software).

What is your decision in the context of this study.