The given points are the vertices of the quadrilateral

By Green's theorem, the line integral is


Answer: 2. To avoid bias
Explanation:
The random sampling can be defined as the method of selecting the samples from the population of interest randomly. The main advantage of this method is to select the samples from the target population and eliminating the bias in sampling. The random sampling is least choice of sampling for research purpose as the researcher wants to choose only selected desired samples for the study.
You just have to find what will make both sides equal. So calculate -4 x (-6+ 5.7)