As nouns the difference between importance and merits

is that importance is the quality or condition of being important or worthy of note while merits is plural of lang=en.

As a verb merits is

third-person singular of merit.

As nouns the difference between deliverance and retirement

is that deliverance is act of delivering, the state of being delivered, or something delivered while retirement is an act of retiring; withdrawal.

As nouns the difference between tart and tartlets

is that tart is a type of small open pie, or piece of pastry, containing jelly or conserve; a sort of fruit pie while tartlets is plural of tartlet.

As an adjective tart

is sharp to the taste; acid; sour.

As a verb tart

is to practice prostitution.

As nouns the difference between importance and roles

is that importance is the quality or condition of being important or worthy of note while roles is plural of lang=en.

As nouns the difference between certainty and decision

is that certainty is the state of being certain while decision is decision.

Isro is likely misspelled.

Isro has no English definition.

As a proper noun NASA

is national Aeronautics and Space Administration, a civilian agency of the government of the United States of America, charged with space and aeronautical research and space exploration.

As nouns the difference between axis and equator

is that axis is an imaginary line around which an object spins (an axis of rotation) or is symmetrically arranged (an axis of symmetry) while equator is an imaginary great circle around the Earth, equidistant from the two poles, and dividing earth's surface into the northern and southern hemisphere.

As proper nouns the difference between axis and equator

is that axis is the alliance (in effect before and during World War II) of Germany, Italy, Japan, and several minor allied countries, which opposed the Allies while Equator is the Earth’s equator.

Bulit is likely misspelled.

Bulit has no English definition.

As a noun construct

is something constructed from parts.

As a verb construct

is to build or form (something) by assembling parts.

As nouns the difference between construct and between

is that construct is something constructed from parts while between is a kind of needle, shorter than a sharp, with a small rounded eye, used for making fine stitches on heavy fabrics.

As a verb construct

is to build or form (something) by assembling parts.

As a preposition between is

in the position or interval that separates (two things), or intermediate in quantity or degree (see the usage notes below).

As an adjective overt

is open and not secret nor concealed.

As an adverb obviously is

in a obvious manner; clearly apparent.