How to express an acre of land with symbols

There is no international symbol for the area per mu
Mu is China's municipal land area unit, one mu is equal to 60 square feet. 15 mu is equal to one hectare

What does this symbol mean?
Is there an a in a circle?
My God! I'm talking about a capital "a" in the circle!

It's like an ammeter symbol

What is the sign of mass in physics?

It's M
Mass is one of the seven basic dimensions in physics, the symbol M
In the international system of units, the basic unit of mass is the kilogram, the symbol kg. At first, the mass of pure water of 1000cm ^ 3 (1dm ^ 3) at 4 ℃ was 1kg. In 1779, a standard kilogram was made of platinum iridium alloy and stored in the International Bureau of Metrology in Paris, France

What is the difference between the symbol of physical quantity and that of unit in physics?

It is not uncommon to use the same letter to indicate both the symbol of physical quantity and the symbol of unit
For example, s is the area of an object and the distance between two places (points)
P. Sometimes it's pressure, sometimes it's power
However, as long as a symbol can express different quantities of two meanings, there can be no conflict
As long as we remember the formulas clearly, we can't confuse them
For example: S = π R ^ 2, s = f / P
W = FS. Here s is the distance
Although there is s in both formulas, they do not interfere with each other
As for W, on the one hand, it represents the sign of physical quantity "work", which is common in formulas, such as w = uit or w = FS; on the other hand, it represents the unit of electric power, which must appear after mathematics, such as P = 900W
There are also two situations that can't disturb each other

Can heat accelerate the motion of electrons in atoms?
As we all know, heat energy can speed up the movement of molecules. Can it speed up the movement of electrons in atoms? Increase the energy of electrons and jump out of the original energy level? Thank you

Of course, heat energy can increase the number of collisions between molecules, thus increasing the internal energy of molecules. Chemical reaction is just because the internal energy changes the energy of electrons, which leads to the absence or excess of electrons in the energy level. If heat energy can not make electrons transition, can most chemical reactions be accelerated by heating? Believe me, I study chemical engineering~
If you feel satisfied, take mine!

What are the differences and connections between the markers and indicators in the principles of statistics?

Mark and index are two different and related concepts. The main differences between them are as follows: 1. Mark describes the characteristics of the overall unit, while index describes the overall characteristics; 2. Mark has quality mark which can not be expressed by numerical value and quantity mark which can be expressed by numerical value, but no matter what index, it is expressed by numerical value

Where does the kinetic energy of electrons in an atom come from?
Be specific

Absorbing photon energy

How to look at the circuit system diagram of electrical construction drawing, what does each symbol mean?

First look at the main control circuit, then look at the auxiliary circuit, pay attention to the protection circuit inside, as for the meaning of symbols, finally look up the electrical engineering design manual, because some symbols in different standard atlas express different meanings

Where does the kinetic energy of electrons around the atomic charge come from?
Why never stop, where does the energy come from, will the energy be exhausted?

The energy comes from the gravitational force between the nucleus and the electron (the nucleus is positively charged and the electron is negatively charged),
Motion is like the moon around the earth, but it depends on gravity
The electron absorbs (emits) light energy and makes a transition You can read high school physics books!

All symbols in building electrical system diagram? What do they mean?

PVC - laying DGL with flame retardant plastic pipe - laying VXG with electrical steel pipe - laying GXG with plastic trunking - laying KRG with metal trunking - laying flexible plastic pipe - laying open laying part code LM - laying ZM along roof truss or lower chord of roof truss - laying QM along column - laying PL along wall - laying along sky

How to express an acre of land with symbols