Good Riddles

Question: I always murmur but never talk, i always run but never walk, and I have a bed but I don't sleep. What am I?

Question: What goes up but never go down?

Question: What do you get when you cross an elephant and a fish?

Question: Why was the woman fired from the car assembly line?

Question: If 1+1=4, 7-3=2, and 5x2=8, then what is half of 19?