can anyone help with this question

1. a. Let X, X,,..., X, denote a random sample of size n from a U(0,0) distribution with p.d.f: f ( x | 0 ) =-, Osx50 (i) Show that 0 =max X, i =1,...n is sufficient for 0. State definition or theorem used. (Note that the Uniform distribution is not a regular exponential family). [8] (ii) Given that O =max X, is also complete, find a UMVUE for 0 . State theorem used. [5]