Having a rough time understanding this chapter, please explain in detail thank you in advance!

Logan, Inc. held 500 shares of treasury stock with a cost of $10 per share. In December, Logan sold 10 shares at $20 per share. The journal entry to record the sale of treasury stock using the cost method would include a (debit/credit) to Treasury Stock in the amount of deblt $200 credit $100 credit $200 debit: $100