| 1. | \(15\) kJ/m3 | 2. | \(20\) kJ/m3 |
| 3. | \(25\) kJ/m3 | 4. | \(30\) kJ/m3 |
| 1. | remain the same. |
| 2. | become \(8\) times its initial value. |
| 3. | become \({1 \over 4}\)th of its initial value. |
| 4. | become \(4\) times its initial value. |
| 1. | \(\sqrt{L_1L_2} \) | 2. | \(\dfrac{L_1+L_2}{2}\) |
| 3. | \(2L_1-L_2 \) | 4. | \(3L_1-2L_2\) |
