Question

q20. what happens when you mix cold water and warm water? *
they begin to mix immediately
cold water rises before they mix
warm water rises before they mix
cold water will push the warm water to the bottom

Explanation:

Warm water is less dense than cold water. According to the principle of buoyancy, less - dense substances rise in more - dense substances. So, when cold and warm water are mixed, warm water rises before they fully mix.

Answer:

Warm water rises before they mix