The movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity

the process by which heat or electricity is directly transmitted through the material of a substance when there is a difference of temperature

a way in which something is usually done.

the emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles which cause ionization

flow of atomic and subatomic particles and of waves, such as those that characterize heat rays, light rays, and X rays. All matter is constantly bombarded with radiation of both types from cosmic and terrestrial sources.

a current in a fluid that results from convection.

The term ionizing radiation refers to those subatomic particles and photons whose energy is sufficient to cause ionization in the matter with which they interact.

none of them

in nature , sea breeze and land breeze are examples of convection currents set up in air in coastal areas

Chimneys are fitted in factories to remove undesirable smoke and fumes . Being hot , and thus lighter these gases rise up and escape through the chimneys.

Ventilators are placed high up the walls of a room . The warm air containing carbon dioxide inside a the room rises up and cooler fresh air flows in through the ventilators

all of the above