Answer:
<h2>Because water can lose and accept H + ions .......</h2>
Not sure the precise concept of "normal observation", but I assume that is observed by "eyes".
Eye observation is basically macroscopic, but when you use a mark, which can be regarded as a point of mass, then it goes to microscopic.
Mark is a reference point which you can compare the relative position change, but with your eyes, first you cannot notice microscopic changes, second the eyes cannot precisely set a stable reference point.
Answer:
The discharge rate is 
Explanation:
From the question we are told that
The diameter is 
The head is 
The coefficient of contraction is 
The coefficient of velocity is 
The radius is mathematically evaluated as

substituting values


The area is mathematically represented as

substituting values


The discharge rate is mathematically represented as

substituting values


Answer:
I thinl it is I'm not sure though