Problem 4. Prove or Disprove. For each part, suppose the functions f(n) and g(n) are asymptotically positive, as defined in Chapter 3 (page 45). Note that for a disproof, you should give a counterexample. 4(a). Prove or disprove: if f(n)=0(g(n)), then 2f(n)=0(28(n). 4(b). Prove or disprove: f(n) is Off(n)). 4(c). Say function f is "asymptotically non-decreasing" if f(n)=f(n+1) for all large enough n. Prove or disprove: if f(n)=(n2), then f is asymptotically non-decreasing