A room inside a recording studio is lined with soft foam in order to absorb the energy of sound waves produced inside the room. How will sound waves interact with the foam? A. The foam will refract the waves, causing their frequency to change
B. The foam will take up some of the waves' energy, decreasing their amplitude
C. The foam will cause constructive interference, increasing the waves' amplitude.
D. The foam will reflect the waves, causing an echo.

It's B

grav potential energy

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia