What is the number of futures contracts that should be shorted on a portfolio if the index level is 1,000, the index futures price is 1,050, the value of the portfolio is $6,060,000, the beta is 1.7, and the futures contract for the delivery is $175 times the index? What would the number of contracts be is the beta increases to 2.1 or declines to 1.3? What is the futures contract for delivery is $210 times the index?