2. A vehicle moves in one dimension with the velocity vs. time graph shown. (2) Over what time intervals is the velocity increasing?
(b) Over what time intervals is the velocity decreasing?
*) Determine the displacement during the interval from t = 2 to t = 5 s.
(d) On the axes below, sketch the acceleration vs. time graph of the vehicle over the
entire time.

What are you asking

Sounds propagates through some kind of medium. usually it's air, but it goes just as well through solid objects like walls, windows etc. a soundwave will compress the (air)molecules in front of it, and if this increased density wave hits your ears, you register it as sound. solid objects like walls are a lot denser than air, this means that they will damp a wave, but also carry it easier.

Carbon dioxide because it consists of one type of molecule.