An introductory section that sets up a lengthy text is a

prologue hope this helps

Explanation:

An introductory section that sets up a lengthy text is a prologue.

Explanation:

A prologue is an introduction or a preface of a literary work. It has relevant pieces of information necessary to the reader before starting the novel. This information is presented in a subtle way to keep the reader's attention and even draw them into the story beforehand.

Both the phrase and definition match. Therefore, the answer is Prologue.

the second option.is correct

the gas pressure p, gas volume v, and gas temperature t are given in the formula:   pv=nrt,

r is the gas constant, and n is the number of gas moles.

if the container is cooled and remains under atmospheric pressure, where r is a constant that does not change, the volume of the container remains the same, the conclusion is drawn that, with all other values ​​unchanged, the number of gas moles n, is decreases.

the right answer is a.