4. On June 29, 2021, Schaum Co. sold merchandise to Welby Corp. for $120,000 on account. The merchandise had a gross margin of 30.0%. Schaum received payment in full on July 15, 2021. Schaum Co. uses the periodic inventory system. a. Show the journal entries needed on June 29 and July 15 for Schaum Co. b. In 2020, Schaum had a beginning balance of $3,000,000 and an ending balance of $3,250,000 in its Inventory account. Annual sales were $18,000,000. The merchandise had a gross margin of 30.0%. Determine the dollar amount of inventory purchased by Schaum during the year