Answer: The placebo group serves as the control group because this group corresponds to the reference point that will be compared to the other group.
Step-by-step explanation:
The control group is a reference point in an experiment they usually never receive any treatment and serves as benchmark to compare other test result which are measured. The control groups also includes individual with similar characteristics like those been tested e.g Age, health history.
Members in a control group are usually given placebos and usually do not know that they are part of the control group. This helps the researcher determine the effectiveness of the study being carried out.
The term above represents the radius of both the circles
Answer:
Option (3)
Step-by-step explanation:
Perpendicular lines: Perpendicular lines are the lines that intersect each other at right angles
Intersecting lines: Intersecting lines are the lines that intersect each other at a point to form angles but vertically opposite angles are equal
Hence , from above conclusion we can write Perpendicular lines must cross to form ninety degree angles, but intersecting lines cross to form angles of varying measures.
Hence , Option (3) is correct answer
