Convection currents<span> are </span>caused<span> by an uneven temperature within something. </span>Convection currents<span>happen within the Earth's magma, water and air. It can happen in anything that is not solid and has parts that are cooler or warmer than other parts.</span>
The stone tool industry being described is the Acheulean. These tools are characterized by hand axes and bifacial blades and were made by many different species of Homos, including Homo erectus and early Homo sapiens.
Answer:
Conductors.
Explanation:
Conductors allow the flow of electrons i. e. the current and where some of the electrons energy gets converted into heat while some electrons energy converted into light. Conductors are the materials which has the ability to allow heat and electricity to flow through them. Metals such as gold, copper, Silver, Aluminum, Mercury, Steel, Iron and salty water etc are good conductors of heat and electricity.
