The answer here is D, and it's kind of obvious. But you probably already knew the answer and are just doing this for piece of mind.
Explanation: Just the fact that we don't know whether or not there even is extraterrestrial life rules out every other answer, without even needing to go in depth.
(Okay, I read your question completely wrong, it's asking for which one of these has been solved isn't it?)
This is tough because all of these other than D have been figured out. Go with the methane atmosphere then.
Answer:
The theory of plate tectonics states that the Earth's solid outer crust, the lithosphere, is separated into plates that move over the asthenosphere, the molten upper portion of the mantle. Oceanic and continental plates come together, spread apart, and interact at boundaries all over the planet. It was proposed by Alfred Wegener.
Explanation:
Answer:
THE SUN AND SOLAR SYSTEM ARE IN THE MILKY WAY GALAXY
(IM GANNA PUT WHAT I LEARNED FOR PART 2)
I LEARNED THAT
1. ITS PART OF THE VIRGO SUPERCLUSTER
2.I LEARNED THAT ITS WARPED
3. IT HAS AN INVISIBLE HALO
Explanation:
CAN I PLEEEEEEEEEEEASE GET BRAINLIEST
IM TRYING TO LEVEL UP
HOPE I HELPED
-ZYLYNNN JADE ARDENNE
Answer:
Starch and fat
Explanation: ATP is for short term energy. ADP is used to make ATP.
DNA stands for Deoxyribonucleic Acid, so it's an acid
