The portfolio manager is about to hedge the market risk where a $10 million portfolio is exposed. The manager is looking to buy the index Put option out of fear that the market will drop significantly over the next six months and the value of the portfolio will fall below $9.5 million. The stock price index is now 500, and one option trades 100 times the index. When the beta value for the market in the portfolio is 0.5, how many put options should be purchased (expressed as + for long and for short)?