Questions

Since, the sentence starts talking about the thought process, R will be the next statement as it is talking about the two factors. Q will be the continuing statement as it carries a relative pronoun which connects both the statement. S follows Q as it discusses the need for a language and P discusses why there is a need for the international language.

The correct formation would be, ‘We can think of two factors which suggest the need for an international language often confused in the public mind’.

Opportunity cost is the cost of other alternative choices for making your interested choice of work. Oppurtunity cost is also called as alternative cost.

For example on a holiday, you have two choices to do, either you can go to movie or a function. And if you chose to go to moavie, the oppurtunity cost of going to movie is the value that would have gotten if you had gone to function.

The law of increasing opportunity costs states that as you increase production of one good, the opportunity cost to produce an additional good will increase.