Google-sheets – How to change many formulas at once in Google Sheets

It will depend upon what else you have in your spreadsheet. Text like "Minutes(Cardinal)" might require care. First I would have the formulae visible (View, All formulae or Ctrl+`).

Then it rather depends upon the formulae, of which you have only provided a single example. A column as the example that had been copied down could be changed with simple Edit, Find and Replace.... of (C with ($C and ;C with ;$C, with Also search within formulae.

With two columns the same (say Cs and also Ds), Search using regular expressions could be applied to save repeating the above for Ds, with finding:

(\()(.) and  
(\;)(.)  

and in both cases replacing with:

$1$ $2  

Two columns for example, but it could be the whole sheet. Unfortuantely that regex introduces spaces into the formulae, though those can then be removed quite easily and in bulk.

So possible, but a peculiar requirement for which they may be a better alternative solution.

Stepped area chart does not support variable width of steps. But you can use the ordinary area chart like this:

The data provided to this chart was as follows. The first column was marked for "use as labels" when inserting the chart.

0.00    0
1.00    0
1.00    1
1.41    1
1.41    2
1.73    2
1.73    3
2.00    3
2.00    4
2.24    4
2.24    5
2.45    5
2.45    6
2.65    6
2.65    7
2.83    7

The idea is that each x value is repeated twice, and each y value is repeated twice, but they are half-step out of sync with each other. So every time we move down the rows, exactly one of two coordinates changes: x (horizontal segment) or y (vertical segment).

For the record, the formulas were =sqrt(floor(row()/2)) and =floor((row()-1)/2) and the chart options were