The gravitational acceleration of a planet is proportional to the planet's mass, and inversely proportional to square of the planet's radius.
So when you stand on the surface of this particular planet, you feel a force of gravity that is
(1/2) / (3²)
of the force that you feel on the surface of the Earth.
That's <em>(1/18)</em> as much as on Earth.
The acceleration of gravity there would be about <em>0.545 m/s²</em>.
This is about 12% less than the gravity on Pluto.
Eric is writing about the cell wall.
Chloroplast is for photosynthesis.
Mitochondria releases energy from respiration.
Nucleus controls the activities of the cell.
But the cell wall supports and gives structure to the cell.