Multiply 2 cm by 100 to convert to meters

When someone slams her books on a table the kinect energy is transferred into vibrations that travel to your ears as sound waves which statement describes the movement of those waves

The graph describes the motion of an object. the object moves with from a to b. it from b to c. it moves with from c to d.

What are similarities and differences of reflection, refraction, diffraction and absorption?