1. What do you notice about the photos on pages 14-15? According to the article, what was their purpose?

“there are three different methods of direction observation with intervention: parrticipant observation structured observation and field experiments . “ hope this

the answer is c. hope this

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.