A long straddle is a combination of buying a call and put option at the same time. Both options have the same strike price and expiration. Assume that the straddle is constructed by European options.

I. Design the payoff diagram of the strategy.

II. A trader enters a long straddle trade on XTB USD 10,000. If both options cost $5 each and at the expiry time the current price is XTBUSB 10,500, when does the trader generates profits? Describe briefly.

III. At the expiry time as above, for every $1 change in the price increase of XTBUSB, Delta () becomes 0.001. What is the long straddle options overall cost change?