The number of energy levels increases as you move down a group as the number of electrons increases. Each subsequent energy level is further from the nucleus than the last.
Typical air flow i believe hope i helped
The answer I believe is now b)2+ because if you so the add and subtract in this you will get 2+
A gravity well is the pull of gravity that a large body in space exerts. The larger the body (the more mass) the more of a gravity well it has. The Sun has a large (or deep) gravity well. Asteroids and small moons have much shallower gravity wells. Anything on a planet or moon is considered to be at the bottom of the gravity well. Entering space from the surface of a planet or moon means climbing out of the gravity well, something that often takes a huge amount of energy. The larger a planet or moon's gravity well is, the more energy it takes to achieve escape velocity and blast a ship off of it.
It would be. 2Fe + 3O2 ——> 2Fe03. You have to make oxygen 6 on both sides in order to balance, then you can do Fe. Which on the right would be 2 by making oxygen 6. Then add the 2 to the other side to balance it.