Answer:
a. True
Explanation:
The statement given regarding salt is correct,
Salt is ionic in nature, as it is composed of a positive ion, i.e. , cation and a negative ion, i.e. , anion.
Salt can be made by the combination of respective acid and base.
There are three nature of salt, acid, base and neutral.
Hence, from the given statement of the question,
The correct option is a. True.
This is an incomplete question, here is a complete question.
In the Bohr model of the hydrogen atom, an electron moves in a circular path around a proton. The speed of the electron is approximately
?
Find the force acting on the electron as it revolves in a circular orbit of radius
.
Answer : The force acting on electron is, 
Explanation :
Formula used :

where,
F = force acting on electrons
m = mass of electrons = 
v = speed of electron = 
r = radius of circular orbit = 
Now put all the given values in the above formula, we get:


Thus, the force acting on electron is, 