Hola!
Percentage Error is a measurement of the discrepancy between an observed and a true, or accepted value.
[ refer the attachment. ]
According to Question,
% error =

× 100
= 2.631 % = 2.7 % (approximately.)
hope it helps!
Letter B
without a medium, there is nothing to compress, hence, no wave. A fast- medium like a gas (air) is easy to compress and allows waves to move through it easily. a slow medium, like a liquid, is still pretty fast, but not as fast as air.
I would believe it to be C. Gold, but I'm not quite sure
The coefficient of static friction between the chair and the floor is 0.67
Explanation:
Given:
Weight of the chair = 25kg
Force = 165 N (F_applied)
Force = 127 N (F_max)
To find: Coefficient of static friction
The “coefficient of static friction” between a chair and the floor is defined as the ration of maximum force to the normal force acting on the chair
μ_s=
The F_n is equal to the weight multiplied by its gravity
∴
=mg
Thus the coefficient of static friction changes as
μ_s=
μ_{s} = 
= 0.67
The unconscious mind plays a large role in Sigmund Freud's psychoanalysis<span>. He discussed the importance of the unconscious mind in understanding conscious thought and behaviour. </span><span>Sigmund Freud
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