To assess the state of business activity of industrial etc.

To assess the state of business activity of the industrial enterprises of different ownership forms were conducted random surveys of business with the following results:
Intervals of values \u200b\u200bof the index of business activity (in points) 0 - 8 8 - 16 16 - 24 24 - 32
The number of enterprises (open joint stock companies) on October 15 on May 8

Construct a frequency distribution histogram. Find the average value of the index of business activity, variance, standard deviation, coefficient of variation. Explain the results.