I have the same question right now and i think that it is D
Answer:

Explanation:
Hello there!
In this case, we can identify the solution to this problem via the Dalton's rule because the partial pressure of helium is given by:

Whereas the mole fraction of helium is calculated by firstly obtaining the moles and then the mole fraction:

Then, we calculate the partial pressure as shown below:

Best regards!
The answer is A. The vibration caused by the waves through the air eventually weaken, which is why sound diminishes easily over distance.
A covalent bond describes two atoms (most likely nonmetals) that share their valence electrons to satisfy the octet rule. Carbon and oxygen are both nonmetals, and they would share electrons with each other through a bond that is not polar enough to be considered ionic. The answer should be B
Answer:
Octasulfur is just S8. Eight S atoms in
a sort of crown shape. Sulfur Dioxide is a gas, SO2. Does that help?
Explanation: