The number 0.00243 has how many significant digits?

this number has a sig digits of 3 because of the 3 zeros

you can't, but you can edit them

sir thomas more, venerated in the catholic church as saint thomas more, was an english lawyer, social philosopher, author, statesman, and noted renaissance humanist. he was also a councillor to henry viii, and lord high chancellor of england from october 1529 to 16 may 1532.