2. Order the functions such that each function is big-O of the next function in the list: (log n), n/1000000, n, 100n + 101, 3", n!, 2"n 3. Use the definition of the fact that f(n) is O(g(n)) directly to prove or disprove that n + 18n + 107 is O(n). 4. Show that 7x is 0 (x). 5. Determine whether the following functions are 2 (x) and whether it is ex: a) f(x)=10 b) f(x)=3x+7 c) f(x)=x+x+1 d) f(x)=5log x e) f(x)=x f) f(x)=x/2