clear handwriting please

Question 4 Let fut} be a function and b E Fl. f is continuous at X = b if and only if : 4.1 ........... (I) 4.2 .............. (l) 4.3 ................. (l) Hint: 4.1, 4.2. 4.3 require you to state the conditions that must be satised for f to be continuous at x = b (Junction 5 Let 4 it2 if x