<span>The plates make up Earth's outer shell, called the lithosphere. (This includes the crust and uppermost part of the mantle.) Churning currents in the molten rocks below propel them along like a jumble of conveyor belts in disrepair. Most geologic activity stems from the interplay where the plates meet or divide.</span>
Answer:B
Explanation:
Given
Distance of astronaut From asteroid x is 
Distance of astronaut From asteroid Y is 
Suppose M,M_x,M_y be the masses of Astronaut , asteroid X and Y
If the astronaut is in equilibrium then net gravitational force on it is zero


cancel out the common terms we get




Explanation:
given,
mass of one planet (m1)=2*10^23 kg
mass of another planet (m2)=5*10^22kg
distance between them(d)=3*10^16m
gravitational constant(G)=6.67*10^-11Nm^2kg^-2
gravitational force between them(F)=?
we know,
F=Gm1m2/d^2
or, F=6.67*10^-11*2*10^23*5*10^22/(3*10^16)^2
or, F=6.67*2*5*10^-11+23+22/3*3*10^32
or, F=66.7*10^34/9*10^32
or, F=7.41*10^34-32
•°• F=7.41*10^2
thus, the gravitational force between them is 7.14*10^2
1 g = 1 ÷ 1000 kg
= 0.001 kg
1 cm³ = 1 ÷ 100 ÷ 100 ÷ 100 m³
= 0.000001 m³
1 g/cm³ = 1 g / 1 cm³
= 0.001 kg / 0.000001 m³
= 1000 kg/m³
The density is 1000 kg/m³.