Out of the four elements shown above – copper, sulfur, helium and mercury – which do you think are metals? Why?

Out of the four elements mentioned - copper, sulfur, helium, and mercury - the metals are copper and mercury.

This is because metals are generally characterized by their ability to conduct heat and electricity, malleability (they can be beaten into thin sheets), ductility (they can be drawn into a wire), and they are usually shiny.

Copper and mercury possess these characteristics. Copper is a good conductor of electricity and is often used in electrical wiring. It is also malleable and ductile. Mercury, on the other hand, is the only metal that is liquid at room temperature. It is used in thermometers because it expands uniformly in response to temperature.

Sulfur and helium, on the other hand, are not metals. Sulfur is a non-metal and helium is a noble gas.