Apharmaceutical company has developed an experimental drug meant to relieve symptoms associated with the common cold. the company identifies 300 adult males 25 to 29 years old who have a common cold and randomly divides them into two groups. group 1 is given the experimental drug, while group 2 is given a placebo. after 1 week of treatment, the proportions of each group that still have cold symptoms are compared. this is an example of

Single blind clinical trail.

Explanation:

In the given case the experimenter is aware of the drug that he is giving to the patients. In this case, the total number of person is divided into two groups.

Then group 1 is given the drug and group 2 is given placebo. So, the patients are unaware of the drugs whether it is place or true drug.

This is known as single blind clinical trial.

answer; i believe the answer is moderate level;

you may having too much sleep.. a good night sleep consists of about 7 hours. more than that could be the reason you're still tired throughout the day.