I think its b because when there is unbalanced forces it accelerates.
Hope this helps you out
Answer:
reactants --> products + thermal energy
Explanation:
Heat is absorbed in endothermic reaction.
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.
Answer:
6 m/s
Explanation:
12m / 2s = 6 m/s
Hope that's the answer you seek.
The force f of the elevator on the man keeps reducing as the elevator keeps going up while the gravitational force mg keeps increasing moving upwards.
<h3>What is an elevator?</h3>
An elevator is an electrical device that lifts people up and down a tall building or structure.
for the elevator to go up, f > mg.
for the elevator to come down mg > f.
Analysis
since the force on the man is f = ma
where a is the acceleration of the elevator, then it means when a increases, f will increase and when it decreases, f would decrease. slowing down means a, is decreasing going up and this reduces the force as the elevator keeps going up.
on the other hand, gravity acts faster on bodies that are slower in motion so since g, increases going up, mg would also increase.
Learn more about forces in an elevator : brainly.com/question/13526583
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