please help me with this question
The complex number u is given by
u = 7 + 4i
3 - 2i
(i) Express u in the form x + iy, where x and y are real. [3]
(ii) Sketch an Argand diagram showing the point representing the complex number u. Show on the same diagram the locus of the complex number z such that |z - u|= 2. [3]
(iii) Find the greatest value of arg z for points on this locus.
i can do (i) and (ii) no problem but i need help with part 3 please
this is question 7 from CIE Maths paper 3 Oct/Nov 2003 which is attached