Which image reflects "hydropower"?

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What is "net zero"?

• measuring method that shows the contrast between created and eliminated emissions.

• it means that a region has completely stopped its emissions of carbon dioxide.

• balance between emissions produced and emissions taken out of the atmosphere.

Sustainable energies would produce:

• electric vehicles, electric heating and vertical farming

• solar panels, bio-gas systems and diesel vehicles

• bio buses, algal bioreactors and traditional energies

What's the best definition for "waste"?

• Food that people consume

• Materials no longer needed

• Elements for recycling

• Money that could be saved

Which precious metals can be retrieved from mobile phones? (more than one answer)

• silver

• rhodium

• gold

• iron

Plants (plural), like seaweed, that grow in or near the water are called ______________.

Which one is the best option for sustainable energy production?

• Wind power

• Geothermal energy

• Biofuel

• Solar energy

• Hydropower