The chart lists four different kinds of atoms. A chart titled Different Kinds of Atoms with the entries calcium, gold, argon, iodine.

What is true about all of these atoms?

They cannot be solids.
They are the largest units of matter.
They are the only types of atoms that exist.
They cannot be divided and still keep the properties of the element.

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.

im srry but ur wrong the answer is d a smooth rock, some red dirt, and an empty bird's nest.

i need with 1.3.2 investigate cycling o2 and co2 apex

we need to see it