Suppose the current spot price is $3. With 50 percent of the probability, the spot price will increase or decrease by 1 dollar for first year and then remain the same as shown in the graph below. t=0 t=1 t=2 Pu=0.5 SO=4 SO=4 SO=3 SO=2 SO=2 Pd=0.5 (c) To make the hedge portfolio risk-free, the value of the portfolio should not vary no matter stock price rises or falls. Please based on the above fact, solve the optimal hedge ratio h* [1 mark] (d) Equivalently, to make the hedge portfolio risk-free, the hedge portfolio should not make profit in one state and make loss in the other, where the state means stock price rises or falls. Please use the optimal hedge ratio solved in (c) to verify this fact. [1 mark] Suppose the current spot price is $3. With 50 percent of the probability, the spot price will increase or decrease by 1 dollar for first year and then remain the same as shown in the graph below. t=0 t=1 t=2 Pu=0.5 SO=4 SO=4 SO=3 SO=2 SO=2 Pd=0.5 (c) To make the hedge portfolio risk-free, the value of the portfolio should not vary no matter stock price rises or falls. Please based on the above fact, solve the optimal hedge ratio h* [1 mark] (d) Equivalently, to make the hedge portfolio risk-free, the hedge portfolio should not make profit in one state and make loss in the other, where the state means stock price rises or falls. Please use the optimal hedge ratio solved in (c) to verify this fact. [1 mark]