P9-3A Rambler Lawn Supply began March with 50 units of inventory that cost $17 each. The sale price of each unit was $36. During March. Rambler completed these inventory transactions:

Units Unit Cost Unit Sale Price March 2 Purchase. 8 Sale.. 13 Sale.. 222 $20 $37 17 36 17 36 1 20 37 17 Purchase. 24 20 37 22 Sale... 31 20 37 29 Purchase. 24 21 39 Required 1. The preceding data are taken from Rambler's perpetual inventory records. Which cost method does Rambler use? 2. Determine Rambler's cost of goods sold for March under the

a. Perpetual inventory system 3. Compute gross profit for March.

b. Periodic inventory system