Required information [The following information applies to the questions displayed below.] Sigfusson Supplies reported beginning inventory of 100 units, for a total cost of $2,000. The company had the following transactions during the month: January 6 Sold 30 units on account at a selling price of $30 per unit. January 9 Bought 20 units on account at a cost of $20 per unit. January 11 Sold 20 units on account at a selling price of $35 per unit. January 19 Sold 30 units on account at a selling price of $40 per unit. January 27 Bought 20 units on account at a cost of $20 per unit. January 31 Counted inventory and determined that 40 units were on hand. Required: 1. Prepare the journal entries that would be recorded using a periodic inventory system. (If no entry is required for a transaction/event, select "No Journal Entry Required" in the first account field.) 2. Prepare the journal entries that would be recorded using a perpetual inventory system, including any "book-to-physical" adjustment that might be needed. (If no entry is required for a transaction/event, select "No Journal Entry Required" in the first account field.) 3-a. What is the dollar amount of shrinkage that you were able to determine in periodic inventory system? 3-b. What is the dollar amount of shrinkage that you were able to determine in perpetual inventory system?