A diagram above shows a person riding a bicycle up a hill. He bikes for 12 minutes, stops to rest for 10 minutes, the bikes for another 8 minutes to reach the top of the hill. What is the biker's average speed? A.9mph B.6 mph C.3mph D.2mph

The percent efficiency of a machine can never be 100% (or greater), because in the real world some energy is always converted into a. heat b. work c. input force d. output force

Using a pedometer, you walk 3000 steps in 20 minutes, so your speed is 150 steps/min. each of your steps is 0.7 m long. what is your speed? 150 steps/min=/s=/h

The experiment was repeated many years later but the gases were mixed in a different type of container. a white solid was obtained which was xenon fluoride. predict whether you think 1) krypton and 2) radon will react with fluorine. explain reasons for your predictions