On July 18, Mike's Mini Mart issued a $35,000, 180-day, 6% promissory note to purchase a new walk-in refrigerator from Tisdale Equipment Company. On July 31, Brian Tisdale needed cash, so he endorsed the note and transferred it to his bank. His bank charges a discount rate of 8%. How many days are in the discount period? a. 179 b. 167 c. 180 d. 168