The Roth family has liquid assets of $10,000, use assets of $150,000 and investment assets of $34,000. They also have liabilities totaling $108,000. If their total liabilities increase by $7,000 over the next year, by how much would the Roth family need to increase their assets in order to have a net worth of $100,000?

a. $7,000
b. $14,000
c. $21,000
d. $28,000