A bat flew 90 kilometers in one evening, returning to its cave after 3 hours.
What was the bat's average speed? A) 30 km/h B) 60 km/h C) 90 km/h D) 270 km/h

Sorry im a little late. I am as well trying to look this up. But i believe you divide 90 by 3 which would give you 60 km/h. So the answer will be B.)

the answer is kevlar

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.