17. How have geologists been able to infer the internal structure of Earth withoug being able to directly observe inside of the Earth?
Geologists use satellite radar and sonar technologies to map Earth's internal layers.
Geologists study different types of rocks from many differtent locations on Earth's
surface
Geologists, like other scientists make educated guesses about Earth's internal
structure based on previous hypothesis.
Géologists analyze earthquake waves as they move through Earth's interior.

hi,

what occurs during a solar eclipse?

there are small tides across earth.

the moon is between earth and the sun.

p.s. im not sure if the first answer is correct because during a solar ecliphse there are spring tides and i dont know if they are the same.

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.