What is the new weight of a 10kg object on a planet that has twice the earths mass. (assume that the radius of the planet is the same as earths)

Weight = (mass) x (acceleration of gravity) .

Acceleration of gravity on a planet's surface is proportional to

                         (planet's mass) / (planet's radius)² .

On Earth's surface, acceleration of gravity is 9.8 m/s² .

Weight of 10 kg mass = (10 kg) x (9.8 m/s²) = 98 newtons.

On the surface of a planet with twice the Earth's mass
all stuffed into the same radius, the acceleration of gravity
would be 19.6 m/s² ... double what it is on Earth.

Weight of 10 kg would be (10 kg) x (19.6 m/s²) = 196 newtons ...
double its Earth weight.

B) raising the temperature and reducing the volume of the gas.|-/ 

Sorry i don’t know what to do