3. Using the formal definition of Big-O, show the correctness of the following statements: (15 points) (a) logn=O(n0.000001) (b) 7n5+8n100=O(n6) (c) log(logn)=O(logn) (d) 2n=O(3n) (e) f(n)=O(f(n)) (f) n1000,000=O(2n)