If the mass and radius of a planet are double those of the Earth,what will be the acceleration due to gravity on this planet compared to the acceleration due to gravity on Earth?

Where will it be profitable to purchase $1$ kilogram of sugar?

The radius of the Earth is about $6400 \; km$ and that of Mars is $3200 \; km$. The mass of the Earth is about $10$ times the mass of Mars. An object weighs $200 \; N$ on the surface of the Earth. Its weight on the surface of Mars will be .......... $N$.

The weight of a body on the surface of the earth is $100\,N$. The gravitational force on it when taken at a height,from the surface of earth,equal to one-fourth the radius of the earth is $..........\,N$.

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.

Assuming the earth to be a sphere of uniform mass density, a body weighs $300 \,N$ on the surface of the earth. How much would it weigh at a depth of $R/4$ below the surface of the earth (in $\,N$)?