What Am I Riddles

Question: I know all, have seen all, yet I am not conscious. Looking back upon me shows mistakes and also good things. Looking in the middle of me shows opportunities to be exploited. Looking forward upon me shows the effects of decision. What am I?

Question: What smells better than it tastes?

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: It is able, but not capable.
It can stop, but not go.
It is dead, but not yet perished.
It's a ghost, but not paranormal.

Is it high, or is it low?

Question: We are just like people. We grow, we get old, we die off. We come in many different colors. Black, white, brown. We come in a army, there are thousands of us, yet we have no war. But we will still die off over the years. What am I?