Answer:
I believe it is 3 and 4. I really hope it is but i am positive :)
Both acids and bases produce a part of a water molecule. Bases dissociate hydroxide (–OH) ions and acids, hydrogen (H+) ions that when combined form water. Both are also very corrosive when they are strong enough that they fully dissociate in water.
Answer:
Never smoke near a place where hydrogen is generated or being used. Remove all possible sources of flame and sparks. Hydrogen should only be generated and used in a well ventilated out door area. Precautions must be taken to remove all possibilities of fire or explosion.
I think this is the answer