Well,
A control in an experiment would basically be the "normal" version of your test subjects.
In a drug testing experiment with people, the control group would be the people who don't take the drug.
In an experiment on the effects of salt on potatoes, the control group would be a potato without salt on it.
So in an experiment to measure the effects of gas additives on fuel, the control would be fuel without additives.
Answer Choices:
a. Technician A only
b. Technician B only
c. Both technicians A and B
d. Neither technician A nor B
Explanation:
a. Technician A only
Answer:
The acceleration of
is 
Explanation:
From the question we are told that
The mass of first block is 
The angle of inclination of first block is 
The coefficient of kinetic friction of the first block is 
The mass of the second block is 
The angle of inclination of the second block is 
The coefficient of kinetic friction of the second block is 
The acceleration of
are same
The force acting on the mass
is mathematically represented as

=> 
Where T is the tension on the rope
The force acting on the mass
is mathematically represented as


At equilibrium

So

making a the subject of the formula

substituting values 
=> 
Answer:
X: Low potential energy
Y: High Potential energy
Z: Flow of electrons
Explanation: From the figure, it's obvious that Z is the flow of electrons, as shown by the arrow demonstrating the direction of the flow. Because of this, we can easily nullify choices B and C.
From the figure, we can notice that Y has more energy stored and X has a lot less, so you can conclude that Y has high potential energy while X has low potential energy.