Explain two ways hydrogen for fuel cell vehicles can be produced

How Do Hydrogen Fuel Cell Vehicles Work? Fuel cell vehicles use hydrogen gas to power an electric motor. Unlike conventional vehicles which run on gasoline or diesel, fuel cell cars and trucks combine hydrogen and oxygen to produce electricity, which runs a motor.

i guess that visual aids present persuasive examples to what you are presenting, some factors would be theme (does it fit with the color, information, what you are presenting), size (can you see it, is it a big enough span of data/information), and overall look of the visual aid.

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a.) travels faster in solids because the particles are closer together.

air is a gas water is a liquid