Doug gave some people street directions, but because they only nodded their heads and didn't repeat the directions back to him, he doesn't really know whether the directions were understood. what type of barrier is present here

The type of barrier that is present in the scenario is feedback. Feedback is where an individual produces reaction or response to a particular thing in which in the scenario above lacks because Doug doesn’t seem to know what feedback are the people giving him.

by using  production possibilities graph.  opportunity costs are key expenses in financial matters and are utilized as a part of registering money saving advantage investigation of a venture. such expenses, be that as it may, are not recorded in the record books but rather are perceived in basic leadership by processing the money costs and their subsequent benefit or misfortune.

what are the statements