Good Riddles

Question: What wears a black suit and watches while stalking?

Question: You were asked to label the light switches for your company. You are in a room, with unlabeled light switches. There are 3 of them, and there are 3 lightbulbs in the next room. You can not travel back and forth. How do you successfully label the lightbulbs???

Question: I am important at the most dangerous times. I can not be seen, heard, or smelled. If you use me too much you would fatally die. What am I?

Question: There once was a king with 3 glasses off water. 2 were completely full and one was half full. What is the king's name?

Question: Wind and cord combine, buzzing in the box. In all this we find, though to some the use is lost. What am I?