In which of these situations is convection most likely the main form of heat transfer? a. warm air from a heater on the first floor of a house moves to the upper floors.
b. the sides of a metal pan become hot when the pan is placed on a stove burner.
c. a person gets a sunburn from lying on the beach too long.
d. an ice cube melts when a person holds it in his hand.

A.   Warm air from a heater on the first floor of a house moves to the upper floors.

Explanation:

As we know that in convection mode of heat transfer the thermal energy is transferred from one point to other point which the actual movement of the medium molecules.

When thermal energy is given to the medium particles then due to difference in the density medium molecules will move from one point to other point along with the thermal energy.

So here we can say that correct answer will be

A.Warm air from a heater on the first floor of a house moves to the upper floors.  

porque la cantidad de gases de efecto invernadero alcanzó un nuevo máximo sin precedentes, causando daños muy graves a esta, por eso es importante monitorearla, para controlar el porcentaje de daños que esta causa y poder reducirlo o mantenerlo.

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.