Suppose I have the following list:

https://pastebin.com/zFin7kkB

and I have a given value of `maxDh` (let's say 0.5) . How can I replace only the values in the second position with a given operation (e.g. `maxDh*5`) only when the values of the first position are greater than `74` and `maxDh` is lower than `1.2` (as in this case)?. For example given that in this example `maxDh=0.5`, then I would get: `{{40,0.0712996},{40.,0.0712996},{40.,0.0712996}......{74.0202,2.5},{74.0404,2.5},{74.2023,2.5}....etc.`

Thank you very much in advanced,