7 In 2020, a firm had current assets of $3,000, total assets of $12,000, current liabilities of $4,000, total liabilities of $7,000, and total equity of $5,000 In 2021, the same firm had current assets of $5,000, total assets of $17,000, current liabilities of $7,000, total liabilities of $10,000, and total equity of $7,000 Find the change in NWC for this firm. Reminder: NWC = CA - CL