The correct option is C.
An atom can be either in the ground state or in an excited state. An atom is said to be in the ground state, if the total energy of its electron can not be lowered by moving one or more electrons into different orbitals. At the ground state, the electrons in the atom have the lowest energy possible and they are stable. On the other hand, an atom is said to be in an excited state, if the energy of its electrons can be lowered by transferring one or more electrons into different orbitals. An atom in an excited state has more energy and is less stable.
Answer:- 
.
Explanation:- Atomic number for fluorine(F) is 9 and it's electron configuration is 
. 
is formed when F loses one electron from it's valence shell.
Second shell is the valence shell for fluorine and so it loses one electron from 2p to form and the electron configuration of the ion becomes .
Answer:
A full moon occurs when the Moon appears as a complete circle in the sky.
Explanation:
- We see it as a full orb because the whole of the side of the Moon facing the Earth is lit up by the Sun's rays.
- The moon shows no visible light of its own, so we only see the parts of the moon that are lit up by other objects.
Answer:
because too much can neutralise the results
The distance that jet covered in 10 min is 125 Km
calculation
distance = speed x time
speed=750 km/h
time= 10/60hrs
=750 x10/60=125 Km
