The coordination number of A = Number of atoms of B

The coordination number of B = Number of atoms of A

So, The Formula is A_yB_x and the ratio of the number of atoms is y : x

The step or position in a nutritive series like food chain is referred to as trophic level.

There are different trophic levels in an ecosystem and food chain. The producers (photosynthetic organisms) form the first trophic level and consumers take up the successive trophic levels.

The plants or producers take up the primary trophic level. The animals that consume plant/producers take up the secondary trophic levels like deer, cow, bee, earthworm. Animals feeding on the animals of secondary trophic level are considered tertiary trophic level. Snake, frog, crow.

Ozone (O₃), or trioxygen, is a triatomic molecule consisting of three oxygen atoms. Ozone is diamagnetic, which means that its electrons are all paired.

Ozone, O is not a linear molecule. Actually, it is bent with an angle that is a little less than 120°. Ozone has fewer lone pairs than water, thus a larger angle between bonds.

Yoghurt is fermented milk. The milk is heated to 80-90°C for half an hour and then it is cooled to 40-43°C and mixed with an inoculum containing Streptococcus thermophilus and Lactobacillus bulgaricus. Preparation of yoghurt takes approximately 4-5 hours. The original flavour of yoghurt and other fermented kinds of milk is of acetaldehyde.

In marine ecosystems, inverted pyramid of biomass can be observed.

When the relationship between producers and consumers in an ecosystem can be represented in the form of a pyramid in terms of biomass, it is called a pyramid of biomass.

It is of two types:

Upright: The amount of biomass in each trophic level decreases as we move from producers to decomposers. Eg. Grassland ecosystem

Inverted: The amount of biomass in each trophic level increases as we move from producers to decomposers. Eg. In a Marine ecosystem like a pond producers (phytoplankton) have lesser biomass compared to consumers (Fishes).

Upthrust is independent of all factors of the body such as its mass, size, density, etc, except the volume of the body inside the fluid. Fraction of volume immersed in the liquid  it depends upon the densities of the block and liquid. 

So, there will be no change in it if the system moves upward or downward with constant velocity or some acceleration. Therefore, the upthrust on the body due to liquid is equal to the weight of the body in the air.

O₃ is a secondary pollutant whereas CO₂ and SO₂ are primary pollutants.

Secondary pollutants are not emitted directly. They are formed from the combination of primary pollutants with some other compound. Examples of secondary pollutants are Ozone, Formaldehyde, PAN (peroxy acetyl nitrate) and Smog etc.

Every coenzyme is a cofactor but every cofactor is not coenzyme. Cofactors can be classified depending on how tightly they bind to an enzyme, with loosely bound cofactors termed coenzymes and tightly bound cofactors termed prosthetic groups.