Answer:
For studying the environmental pollution caused by industries, samples taken from 225 industries which is the 75 % of the industries. So the population size is 225. The sample size should be taken as much you want. More samples will be taken more accurate results will be gained. I take 20 samples, this number should be increased up to 100 samples. If sample size is 20 so 550 samples will be taken from 225 industries for determining the pollution caused by these industries..
Explanation:
