Grinding pepper is a physical change
might be 140mph, so that is a guess that i just made so plz let me know if im wrong or correct
The answer is a because tjhey do move at a molecular movemn
Answer:
No, the farmer is not able to move the mule.
Explanation:
Mass =100 kg
Force=F=800 N
The coefficient between the mule and the ground=

Static friction force,f=
Normal force=N=mg
Static friction force,f=
Using 
F<f
Static friction force is greater than applied force.
Therefore , the farmer is not able to move the mule.