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4) The following equation uses the time since a person's last meal (x) and the number of calories consumed at the next meal (y): y = 12.5 +109x. The correlation coefficient is r = 0.987 and the average calorie consumption was 504 cals. How many calories would you expect this person to consume on average when 6.5 hours have passed since the last meal?
A) 708.5           B) 721          C) 650           D) 712          E) 504