Pleasure in practice

Question: I move faster in certain solids, but slower in certain gases. I am typically broken by objects with large masses. I can be used as for pleasure, practice, and even an alarm. If used excessively, I can cause harm. What am I?

Question: What tastes better than it smells?

Question: What goes in the water black and comes out red?

Question: What asks but never answers?

Question: I have 6 faces and 21 eyes, but can't see a thing. What am I?

Question: I live in water, but not in the same place. Sometimes it’s drinkable and other times it's not. I am either a hunter or gatherer. I am known for being gentle and easy, but I don’t live long. You will know me by my large eyes and goofy lips. People know me by my slimy body. I can be found in your house or out in the wild but never in between. I am friendly so I will likely be your friend in school. What am I?