All waves consist of a continuous series of
pulses
circles
compressions
rarefactions

Well heck sorry this is so late

All waves consist of continuous series of Pulses

The correct answer is pulses.

Explanation:

Wave is a disturbance which carries energy from one particle to another. Wave is a continuous disturbance.

Pulse is a single disturbance. It travels through one point to another.

Sound wave consists of rarefaction and compression. It need medium to travel.

In the circular wave, the particles move both parallel and perpendicular to the motion of the wave.

Therefore, all waves consist of a continuous series of the pulses.

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.

the answer is c. the lower legs are levers, and the knees are fulcrums. the ankles hold the loads.