What are two ways you could increase the magnification (increase the size of the image) in the situation shown below?
Lens and candle
A. Move the candle to the right, or the focal point to the left.
B. Move the candle to the right, or the focal point to the right.
C. Move the candle to the left, or the focal point to the left.
D. Move the candle to the left, or the focal point to the right.

the plateau is likely to turn into a desert do to corrosion.

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.