In phase would mean both waves are at a positive peak, out of phase would mean one is at a positive whilst the other is at a negative. Out of phase would mean the waves cancel each other out
For number one the answer is Iodine because it is in the same group as fluorine. For number two the answer is Germanium for the same reason. For number three the answer is Aluminum for the same reason.
Answer:
to produce electricty three ways you have the water wheel the wind mill and solor panels
Explanation:
-40 c = -40 f but k would be 233.15
