This is true otherwise cancer patients would have a hole in them and so would the hulk ;)
No, the elements are not always transparent.
<u>Explanation:</u>
The elements become transparent when the light passes through those elements. Transparency is caused because of the transmission and the passing of the light waves through these elements.
But the metals do not become transparent even when the light waves pass through these metals. Metals do not become transparent because the refractive index in them is very big.
Dichotomous keys consist of a series of statements with two choices in each step that will lead users to the correct identification. So I believe your answer would be A.
Answer:
the answer is O²- hopefully
