Is Trump right about the U.S. 'subsidizing' Canada?

Donald Trump has repeatedly claimed the United States is 'subsidizing' Canada 'to the tune of $100B.' Where does that number come from? And is Canada really getting a free ride from the U.S.? Andrew Chang dives into the math, the money, and the politics of the Canada-U.S. trade relationship to uncover how much — if any — of what Trump says is actually true.

Andrew Chan on About That, CBC News