Using the concept of accounting equation, compute missing figures from the following:
1. Assets = $100,000, Liabilities = $40,000, Owner’s equity = ?
2. Assets = ?, Liabilities = $20,000, Owner’s equity = $30,000
3. Assets = $120,000, Liabilities = ?, Owner’s equity = $80,000
4. Assets = ?, Liabilities + Owner’s equity = $300,000