What was the purpose of testing unwashed hands?

Micah is studying child behavior in playgrounds throughout the world. he wants to see how the children react when teachers select the same child to be the first to use each piece of equipment. which approach is micah is using?

Whether or not a given study has the possibility of causing harm to participants:

The internet is controlled by: (select one): a. statutes and court cases in federal and state courts in the united states. b. the advanced research projects agency (arpa) and the u. s. department of defense. c. no single government or organization. d. google, yahoo, and the other search engines which have proprietary interest in the content thereon.