Instruction 7-4 According to a Survey,only 15% of Customers Who Visited the Visited

Short Answer

Instruction 7-4
According to a survey,only 15% of customers who visited the web site of a major retail store made a purchase.Random samples of size 50 are selected.
-Referring to Instruction 7-4,the standard deviation of all the sample proportions of customers who will make a purchase after visiting the web site is ________.