1. A box spread is made of combining two common portfolios. Call them Thing 1 and Thing 2. Thing 1 is built by buying a call and selling another call with higher K than the first. Thing 2 is built by selling a put, and buying another put with higher K than the first. a) Draw one payoff diagram for buying a call and selling another call with higher K. Add to get the payoff diagram of Thing 1. b) Draw one payoff diagram for selling a put and buying a put with higher K. Add and name. c) Draw your answer to a) and your answer to b) in one payoff diagram. Show the payoff diagram of combining "both Things." This is called a box (it does not look like a rectangle). Note not needed to answer: This is an arbitrage strategy, not always profitable. But when it is profitable, it is also riskless