B) Metalloid because that's a mixture of the other two.
Answer: The new pressure is 3 psi.
Explanation:
Given:
= 12 psi, 
= ?, 
Formula used is as follows.

Thus, we can conclude that the new pressure is 3 psi.
Answer:
The answer is C
Explanation:
This is the answer because it is the only way that it is okay to split in half.