What is the output of the following java function when called as f(1,25,25)?

Int f(int a, int b, int n){ int mid =(a+b)/2; if ((mid*mid <=n) && (n< (mid+1)*(mid+1)) return mid; else If (mid*mid>n) return f(a,mid-1,n); else return f(mid+1,b,n); }

B.)

Is the following function tail-recursive?

Acker(m,n){ if(m=0) n+1 else if(n=0) Acker(m-1,1) else Acker(m-1,Acker(m,n-1)) }