After seeing all the other topology problems be left out to dry, I'm not exactly confident Ill get help, but ill try anyway.
So heres a photo of my problem, since im not the best at latex
ok i get that we have to start with let > 0 then we should have > 0 as well right? well after that im seriously sunk, cause I dont know what we would use as as I: (X, d*). I assume whatever we use as that is the one we set < then since its a function to (R,d) it must have |t-a|< but even if all that is right, i wouldnt know what to do there. Any help would be amazing