Suppose that the standard deviation of monthly changes in the price of commodity A is $4.7. The standard deviation of monthly changes in a futures price for a contract on commodity B (which is similar to commodity A) is $6. The R-square of a regression of change in commodity prices on the change in futures price is 91%. What hedge ratio should be used when hedging a one month exposure to the price of commodity A? Please use two decimal places for your answer. Please use two decimal places for your answer.

The answer is 0.75 please explain.