The correct excluded value is 2.
Answer:
When it is small & when the sample has things that are different from the population.
Step-by-step explanation:
A small sample has less chance of accurately reflecting a population & too many variables can also negatively influence the study.
B= 20°
and c = 160°
b is equal to the given angle, b = 20°
c is 180 - 20 = 160°