The accountants of Coca-Cola just determined using the regression method that soybean futures barely qualify for hedging its exposure to variations in cost of goods sold( R-squared = 0.81). What can you conclude about the correlation between soybean futures price changes and cost of goods sold (COGS) changes?
a) It equals 0.90
b) It equals 0.81
c) It equals 0.66
d) Its absolute value equals 0.66