A straight, smooth tunnel is dug through a uniform spherical planet of mass density . The tunnel passes through the center of the planet and is perpendicular to the planet’s axis of rotation, which is fixed in space. The planet rotates with a constant angular speed ω such that objects in the tunnel have no apparent weight. What is the required angular speed ω of the planet?

that would be b i just took the test : )

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

weight is the answer i just took the test