sara went to the zoo with --- freinds today. --- loves animals. when --- were done watching the animals all of felt hungry.

answer: do

the 'italicized phrase' is a noun clause that is used as a direct object.

i believe it’s the first one, but it could be the second! not the third or fourth.

explanation:

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.