(4) slate because it is the strongest
<span>c. Passing electric charge through the reactants Is the answer to you're question.
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That is correct c
Explanation
You have to think about the fact that hot air is constantly being blown up elevating the balloon once that air is taken away it's up to the steering and the wind after that. I know that probably doesn't help did you want to know the science part?
Magnet to remove the iron, filter paper (or some filter that could trap sand) to remove the sand, and heat up the salt and water, causing the water to evaporate to separate them.
