Under what circumstances can witnesses before congress legally refuse to answer questions

Which was not a primary motivation for republicans to promote congressional reconstruction over those policies proposed by lincoln and johnson

In one to two paragraphs, compare and contrast the american, french, and mexican revolution.

Which is the main inference that can be drawn from adam smith's book the wealth of nations? a) for an economy to work flawlessly, it shouldn't have to serve and moral goals.b) the government must control a free-market economy, or economic problems will arise.c) a free-market economy works well only without the government's interference. d) free trade will only hurt economies and should be stopped by governments.