The volume of the liquid shown is ...

Here are the solutions to the questions:

8. The diagram shows the Sun, then the Moon, then the Earth, all aligned in a straight line. When the Moon is positioned directly between the Sun and the Earth, it blocks the Sun's light from reaching the Earth, causing a solar eclipse. A lunar eclipse occurs when the Earth is between the Sun and the Moon. The correct option is C.

   $$\boxed{\text{C}}$$

9. The diagram shows the Sun followed by three planets labeled 1, 2, and 3. In our solar system, the order of the first three planets from the Sun is Mercury, Venus, and Earth.

   • Planet 1 is Mercury.
   • Planet 2 is Venus.
   • Planet 3 is Earth. The correct option that matches this sequence is A. The correct option is A.
   $$\boxed{\text{A}}$$

10. The diagram shows a measuring cylinder with liquid. The major markings are at 5ml intervals (e.g., 10ml, 15ml, 20ml). Between each 5ml interval, there are 4 smaller lines, which means each small line represents 1ml ($5 \text{ ml} / 5 \text{ intervals} = 1 \text{ ml/interval}$). The liquid level is exactly on the first small line above the 15ml mark. Therefore, the volume of the liquid is $15 \text{ ml} + 1 \text{ ml} = 16 \text{ ml}$. The correct option is C.

    $$\boxed{\text{C}}$$