Coulomb's law describes how the charge on and distance between two particles affect the electric force between them. Which situation will result in
the two particles being repelled by each other?
O A. Decreasing the distance between them
B. Increasing the distance between them
O C. Both particles having a negative charge
D. One particle having a positive charge and the other a negative
charge

d. air pressure decreases as altitude increases.

i would like to make dinner for my mom, dad, and sister

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.