I keep getting an error message when i put the '' '' sign in the formula as shown below. Please what can i do r what are my doing wrong

Hi Daryl-Palma Asongu Nguatem, Your answer looks perfectly OK. The only way I can get an error, similar to yours, is if I have type TWO single ' (apostrophes) instead of using the " (double quote) when required. As you can see, it is hard to tell the difference. '' '' - this is four single ' apostrophes with a space between each two. " " - this is two double quotes " with a space between. Hope this fixes your error. Kind regards, Kev T.