I would say vibrations, but is there choices?
The answer is A. Atoms. You're welcome. ;)
Answer:
The electronic configuration of Fe2+ is 1s2 2s2 2p6 3s2 3p6 3d6 and Fe3+ is 1s2 2s2 2p6 3s2 3p6 3d5. Fe2+ contains 2 fewer electrons compared to the electronic configuration of Fe.
Answer:
2.84403 seconds
2.91483 seconds
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration due to gravity = 9.81 m/s²
It takes 2.84403 seconds to reach the highest point
![v^2-u^2=2as\\\Rightarrow s=\frac{v^2-u^2}{2a}\\\Rightarrow s=\frac{0^2-27.9^2}{2\times -9.81}\\\Rightarrow s=39.67431 m](https://tex.z-dn.net/?f=v%5E2-u%5E2%3D2as%5C%5C%5CRightarrow%20s%3D%5Cfrac%7Bv%5E2-u%5E2%7D%7B2a%7D%5C%5C%5CRightarrow%20s%3D%5Cfrac%7B0%5E2-27.9%5E2%7D%7B2%5Ctimes%20-9.81%7D%5C%5C%5CRightarrow%20s%3D39.67431%20m)
The ball will travel 39.67431+2 = 41.67431 m while going down to the ground
![s=ut+\frac{1}{2}at^2\\\Rightarrow 41.71479=0t+\frac{1}{2}\times 9.81\times t^2\\\Rightarrow t=\sqrt{\frac{41.67431\times 2}{9.81}}\\\Rightarrow t=2.91483\ s](https://tex.z-dn.net/?f=s%3Dut%2B%5Cfrac%7B1%7D%7B2%7Dat%5E2%5C%5C%5CRightarrow%2041.71479%3D0t%2B%5Cfrac%7B1%7D%7B2%7D%5Ctimes%209.81%5Ctimes%20t%5E2%5C%5C%5CRightarrow%20t%3D%5Csqrt%7B%5Cfrac%7B41.67431%5Ctimes%202%7D%7B9.81%7D%7D%5C%5C%5CRightarrow%20t%3D2.91483%5C%20s)
The ball takes 2.91483 seconds to hit the ground after it reaches its highest point.