Question: Consider the following data set:

a. Construct a frequency distribution using classes of -1 0 up to 0,0  up to 10, etc. How many of the observations are at least 10 but less  than 20?
b. Construct a relative frequency distribution and a  cumulative relative frequency distribution. What percent of the  observations are at least 10 but less than 20? What percent of the  observations are less than 20?
c. Graph a relative frequency polygon. Is the distribution symmetric? If not, then how is it skewed?