Concerning the vocabulary in the text III, it can be...

“cheerfully” (line 8) is synonymous with selfishly.

“pursue” (line 10) means the same as observation.

“widely” (line 17) is an exact synonym of tentatively.

“revenues” (line 20) means precisely the same thing as taxation.

“follow” (line 22) can be replaced in this particular context by stick to.