When the volume of a gas is changed from 986 mL to mL,
the temperature will change from
765 K to 315 K.

THE NEW VOLUME OF THE GAS IS 406 mL WHEN THE TEMPERATURE CHANGES FROM 765 K TO 315 K.

Explanation:

When the temperature changes from  765 K to 315K, the volume has changed from 986 mL to?

V1 = 986 mL = 0.986 L

T1 = 765 K

T2 = 315 K

V2 = unknown

Using Charles' equation of gas laws;

V1 / T1 = V2 / T2

Making V2 the subject of the formula:

V2 = V1 T2 / T1

V2 = 0.986 * 315 / 765

V2 = 0.406 L

V2 = 406 mL

So therefore, the volume of a gas changes from 986 mL to 406 mL as a result of a change in temperature from 765 K to 315 K.

i think it's c. i'm not sure but i think so.