If you add all the terms of the LHS of equality, then the last letter of the sum written in words would give you the RHS.

1 + 1 + 1 + 1 = 4 = FOUR

2 + 2 + 2 + 2 = 8 = EIGHT

3 + 3 + 3 + 3 = 12 = TWELVE

4 + 4 + 4 + 4 = 16 = SIXTEEN

So, following the same pattern.

5 + 5 + 5 + 5 = 20 = TWENTY

That gives us our answer to 5 5 5 5 =  "Y".

The nucleus of a cell contains chromosomes, which carry genetic information in a long molecule called DNA.

Genes are regions of DNA that carry the code to control a particular cell activity or the production of a particular protein.

You have to actually count all the balls in the pyramid.
Simple way is to count the balls in each level.

So lower most level lets say 1st level has 4 x 4 balls; i.e. 16 balls
Similarly 2nd level has 3 x 3 balls; i.e. 9 balls.
3rd level has 2 x 2 balls; i.e. 4 balls.
The top most level has just 1 ball.

So the total number of balls is 16+9+4+1 = 30.

So the image has 30 Balls in all.

Grasslands are found in most ecoregions of the Earth.

For example, there are five terrestrial ecoregion classifications of the temperate grasslands, savannas, and shrublands ecosystem, which is one of eight terrestrial ecozones of the Earth's surface.

Bond Order  = 1/2[ Nb - Na]

where

Nb = Number of electrons in bonding molecular orbitals.

Na = Number of Electrons in antibonding molecular orbitals

Bond Order of N2⁺:

Total number of electrons: 13

Electronic Configuration= :σ1s² σ*1s² σ2s² σ*2s² π 2py² [π2pz² σ2px1 ]

Bond Order = [9-4]/2 = 5/2 = 2.5.

Methane is the main component of biogas and natural gas.

The given words are related in a way that, an optimist is a person whose outlook is cheerful. Similarly, a pessimist is a person whose outlook is gloomy.

The answer is not (b) because a pessimist does not have to be mean. Options (c) and (a) are incorrect because neither words describe the outlook of a pessimist.

Hence, Optimist is to cheerful as Pessimist is to Gloomy.

The President is the highest officer in the country. Similarly, Governor is the highest officer of the state.

Hence, Country : President :: State : Governor.