An absolute reference. An absolute cell reference.
One way is that you can make the cell reference an absolute reference. So cell A1 would be typed as $A$1 in the formula. Any particular formula that is being copied is usually copied either across or down, but rarely both. Because of this, you can actually use a mixed reference as the other option. If the formula is to be copied down, then you lock the row part of the reference, so it would be A$1 as the reference. If it is being copied across, you lock the column part of the reference, so it would be $A1 as the reference. As most people aren't as familiar with mixed references, they usually use absolute references anyway. The answer to your question is absolute and mixed.
If you want to copy a formula from one cell to another (or fill down) without Excel changing the cell references automatically, you'll need to write the cell references with dollar signs included for absolute referencing. Eg: the reference '$D3' locks the reference to column 'D' but allows the row to change when the cell is copied. Eg: the reference 'D$3' locks the reference to row '3' but allows the column to change when the cell is copied. Eg: the reference '$D$3' locks the reference to column 'D' and row '3', so the cell reference cannot change at all when the cell is copied. While you are typing in a cell reference, pressing the 'F4' key will cycle through the combinations for you, so you don't need to type the dollar signs yourself.
A relative cell reference is one that will change to a different cell if you copy the formula. An absolute reference is one that will always use the same cell. For example, say you have a percentage in cell B1 that you want to add to all the cells from A3 down. In cell B3 you could use the formula '=A3*(1+$B$1)'. If you copy this formula to the cells below B3, the reference to A3 will change to be the cell immediately to the left, because it is a relative cell reference. By adding the $ symbol before the B and the 1, however, an absolute reference is created. It will always refer to cell B1.
What determines what type of reference a cell is, is how it is typed, not what happens when you copy it. It is the type of reference that influences how it changes when it is copied, not the other way around. If the formula does not change at all, it would be an absolute reference. The cell references would all have 2 dollars, like $C$5. If it does change, it can be either a mixed or a relative reference. A mixed reference will have one dollar sign, either $C5 or C$5. What direction it is copied will and how it changes, is determined by which dollar you have. The first dollar locks the column, and the second dollar locks the row. A relative reference has no dollars. Copying a formula from C13 to D13, will change the column references only, so if the cell reference is the first kind of mixed, then it won't change.
If a formula is copied across the column references will change, but the row references will stay the same. So for example C3 would become D3, then E3, then F3 and so on. The column letter is changing, but the row number is not.
If you copy the content of cell B4 to cell C6, the resulting cell reference in C6 will be adjusted based on the relative position of the cells. Since C6 is two columns to the right of B4 and in the same row, C6 will reference the value in B4 directly as it is a relative reference. Therefore, C6 will display whatever value or formula was originally in B4.
An absolute reference.
only d formula will b copied not the reference..
first
Normally it would be a relative address, but depending on what you want to do with the formula, you could have it as an absolute or mixed cell reference. If the cell reference is the same as the cell that the formula is in, you will have a circular reference.
Because for every cell there are many mitochondria within it so for the daughter cell to have the same amount of mitochondria all their DNA must be copied. but there is only one set of DNA within the nucleus of the cell for the cell itself so that only needs to be copied once. if that makes any sense?