Formulate a rule for mixed links.

If, when copying a formula, it is necessary that the column number does not change, then it is necessary to put a $ sign in front of it, if it is necessary so that the line number does not change, then the $ sign is placed before the line number.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.