Plz 50 points and brainliest but give me the true answer with steps
At 200 K, the molecules or atoms of an unknown gas, X, have an average velocity equal to that of Ar atoms at 400 K. What is X? (Assume ideal behavior.)
A) He
B) CO
C) HF
D) HBr
E) F2

Light travels through space at 186,282 miles per second and it takes about 1.3 seconds for light to travel from the moon to earth. which of the following is the correct method of finding the distance, in miles, between the moon and earth? add 186,282 and 1.3 divide 186,282 by 1.3 multiply 186,282 by 1.3 subtract 1.3 from 186,282