Floating eggs

This task is about flotation.

Question

Matu showed his friends an egg trick.

He had three glasses. One contained very salty water, another tap water, and the third had equal amounts of very salty water and tap water. He then lowered an egg into each glass.

This is what his friends saw:


     Glass A            Glass B             Glass C   

a)  What 'kind' of water is in Glass B?
    • Tap water.

    • Very salty water.

    • Half tap water and half very salty water.

    • It is not possible to tell.

b) Whether an object floats is related to the density of the liquid and the object. Explain why the egg floats in Glass B.