Answer :Force is exerted by the Earth on the rock is 280 N .
Given :
Mass of rock falling falling , m = 28 kg .
Acceleration due to gravity ,
.
We need to find the force exerted by the earth on the rock .
Let force exerted be F .
Now , we know by Newton's Law Of Motion .
F = ma .......( 1 )
Here , m is mass and a is acceleration in this case it is
.
Putting all these value in equation( 1 ) we get ,

Therefore, this is the required solution .
The best predictor of the radioactive nature of an isotope is the neutron-to-proton ratio of the atom. Isotopes are atoms of elements having the same number of protons however they don't have the same number of neutrons.
the strength and vitality required for sustained physical or mental activity.
Explanation:
By the end of the section, you will be able to:
Apply problem-solving techniques to solve for quantities in more complex systems of forces
Use concepts from kinematics to solve problems using Newton’s laws of motion
Solve more complex equilibrium problems
Solve more complex acceleration problems
Apply calculus to more advanced dynamics problems
<h2 /><h3>through this steps you will get the answer.thank you</h3>