According to a 2011 study on the promotion, Dartmouth College Tuck School of Business determined that a Free Burrito Day pays for itself in about 15 days.

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Dartmouth College's Tuck School of Business updated its recommendation form this year, fine-tuning questions to better assess EQ.

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"These things are never as seamless as they seem, " said Thomas Lawton, a professor of business administration at Dartmouth College's Tuck School of business.

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