5. [6 pts] Determine whether each of these functions is O(x2). a. f(x)=152x+11 b. f(x)=3x2+13126 c. f(x)=6x4/3 d. f(x)=2x e. f(x)=xx 6. [4 pts] Consider the following sets and answer the following questions. a. {1,2,3,4,,97,98,99,100} b. {1,3,5,7,,97,99} c. {2,4,6,8,,96,98,100}