$A$ spring balance is graduated at sea level. If a body is weighed with this balance at consecutively increasing heights from the Earth's surface,the weight indicated by the balance:

At what distance above and below the surface of the earth will a body have the same weight? (Take the radius of the earth as $R$.)

If $g_E$ and $g_M$ are the accelerations due to gravity on the surfaces of the earth and the moon respectively and if Millikan's oil drop experiment could be performed on the two surfaces,one will find the ratio (electronic charge on the moon / electronic charge on the earth) to be

The height at which the weight of a body becomes $\left(\frac{1}{9}\right)^{\text{th}}$ of its weight on the surface of the Earth is $(R = \text{radius of Earth})$: (in $R$)

Given below are two statements:
Statement $I:$ Rotation of the earth shows effect on the value of acceleration due to gravity $(g)$.
Statement $II:$ The effect of rotation of the earth on the value of $g$ at the equator is minimum and that at the pole is maximum.
In the light of the above statements,choose the correct answer from the options given below.

If the density of the earth is doubled keeping the radius constant,find the new acceleration due to gravity (in $m/s^2$)? $(g = 9.8 \ m/s^2)$