Which improves air circulation in forced air heating? a, radiation b, conduction, c, convection

Convection

Explanation:

As we know that in convection mode of heat transfer the medium molecules is transferred from one part to other part along with the thermal energy stored with them.

Here when heat is given to the medium then due to temperature gradient density of medium will change and this will lead to a movement of medium particles from higher density to lower density region.

This is known as convection mode of heat transfer and this mode of heat transfer can be increased by forced convection of medium particles.

So here air circulation in forced heating is an example of CONVECTION

b) 10 minutes

girls stopped for 10 minutes.