Ignoring reflection at the air-water boundary, if the amplitude of a f=1.1ghzf=1.1ghz incident wave in air is v0=15v/mv0=15v/m at the water surface, determine the depth that make the electric field down to vmin=2μv/vmin=2μv/my. water has μr=1μr=1 and at 1.1ghz 1.1 ghz, εr=70εr=70 and σ=1.5s/mσ=1.5s/m.

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.

i am pretty sure it is c because when people are closer together, they cannot move as freely. picture being in a mostly full elevator, for instance. the people are right next to you, and you can barely move.