The statement about ADHD that is true is: "ADHD has no clear physical symptoms that can be detected via an x-ray or blood test"
<h3>What is ADHD?</h3>
This is an acronym for a kind of mental disorder that is called Attention Deficit Hyperactivity Disorder (ADHD).
Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental psychiatric condition.
It is characterized by challenges concentration, excessive activity, or difficulty restraining behavior that is inappropriate for a man's age.
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Considering the definition of percentage by mass, the sample of pure lithium nitrate contains 7.99% lithium by mass.
<h3>Definition of percentage by mass</h3>
The percentage by mass expresses the concentration and indicates the amount of mass of solute present in 100 grams of solution.
In other words, the percentage by mass of a component of the solution is defined as the ratio of the mass of the solute to the mass of the solution, expressed as a percentage.
The percentage by mass is calculated as the mass of the solute divided by the mass of the solution, the result of which is multiplied by 100 to give a percentage. This is:

<h3>This case</h3>
Because percent by mass indicates the ratio of solute to solution based on mass, if the sample has twice the mass of the first sample, the ratio remains constant.
So the percentage by mass is the same.
That is, the sample of pure lithium nitrate contains 7.99% lithium by mass.
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The classification of each of the elements into nonessential element, essential bulk element, or essential trace element are as follows:
Nonessential elements:
Essential bulk elements:
- Carbon,
- Nitrogen,
- Calcium,
- Hydrogen
Essential trace elements:
The complete question
The elements are: Hydrogen, iron, Copper, Nitrogen, Helium, Carbon, Aluminum, Calcium, Argon
<h3>What is Essential and Nonessential Elements?</h3>
Nonessential elements as the name implies are elements which are not necessary for the functional routine of the body and hence are not included in diets.
Essential bulk elements are elements which are needed for the proper functioning of the body and hence are required in relatively large amounts.
Essential trace elements are required in minute quantities in the body.
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The list is the best data validation that you should use if you want to restrict the values to a specific set.
<h3>What is data validation in a spreadsheet?</h3>
This is a feature in a spreadsheet such as excel that helps to control the entries that the users are allowed to input in a cell.
You can use this excel feature to ensure that a value is a number that is between 1 and 5.
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<u>Complete question:</u>
You want to restrict the values entered in a cell to a specified set, such as hop, skip, jump. Which type of data validation should you use?
database
list
input range
custom
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