Jacques has plans to go to a play and already has a $50 nonrefundable, nonexchangeable, and nontransferable ticket. Now Kyoko, whom Jacques has wanted to date for a long time, asks him to a concert. Jacques would prefer to go to the concert with Kyoko and forgo the play, but he doesn't want to waste the $50 he spent on the play ticket. From the perspective of an economist, if Jacques decides to go to the concert with Kyoko, what has he just done