Sometimes you are able to hear your echo in rooms due to the acoustics of the structure. If you call out 'hello' in a room and hear the echo 10 seconds later, how large is the room?

The material that keeps its new shape after it is stretched is called?

Chemical energy is a form of energy. a. heat b. kinetic c. potential d. electromagnetic

If a rock is thrown upward on the planet mars with a velocity of 12 m/s, its height (in meters) after t seconds is given by h = 12t − 1.86t2. (a) find the velocity of the rock after two seconds. m/s (b) find the velocity of the rock when t = a. 12−3.72a m/s (c) when will the rock hit the surface? (round your answer to one decimal place.) t = s (d) with what velocity will the rock hit the surface? m/s