Answer:
The answer is below
Explanation:
Z score is a score used in mathematics to determine by how many standard deviations the raw score is above or below the mean. The z score is given by:
The area under the curve is dependent on the z score. The higher the z score, the higher the area under curve and the lower the z score, the lower the area under curve.
a) The area under curve (z score) is inversely proportional to the standard deviation. If the standard deviation is increased, the z score decreases thereby reducing the area under the curve.
b) If the standard deviation is decreased, the z score increases thereby increasing the area under the curve.