Verbal Reasoning - Mental Ability Questions

Clearly, the numerators of the fractions in the given sequence follow the series of 2, 3, 5, 7,... and the denominator follows 3, 9, 27, 81, 243, ...
Then, the next term in the given sequence is  935 = 9243 = 127 .

Letters in the word           Letters in the alphabet

$$\begin{gathered} CHA \\ - - \end{gathered}$$                            $$\begin{gathered} CBA \\ - - \end{gathered}$$

$$\begin{gathered} RS \\ -- \end{gathered}$$                             $$\begin{gathered} RS \\ -- \end{gathered}$$       

The letter of the word are written in a reverse order and then each letter is moved one step backward to obtain the code.

Lethargic means "sluggish", kind of inactive

Vital means full of energy, lively

So, they are antonyms.

So, for the 2nd part of the analogy, you are looking for a antonym to trite

Trite means lacking originality or freshness. Overused. Kind of like a cliche

So, an antonym could be original, unique, innovative.

A is a male and married to B. So, A is the husband and B is the wife. C is the brother of A. D is the son of C. E, who is the sister of D will be the daughter of C. B is the daughter-in-law of F whose husband has died means F is the mother of A. 

A is a male. B. the wife, is female. C. the brother, is male. D. the son, is male. E, the sister, is female. F, the mother, is a female. So, there are three males.