True or false:

a. 2n is O(n)

b. 2n is (n)

c. 2n is (n)

d. 3n^2 + 3n is O(n^3)

e. 3n^2 + 3n is (n^3)

f. 3n^2 + 3n is (n^3)

g. n is O(2n)

h. n^2 is (n^2 + 2n + 1)

i. log n^2 is (log n^3)

j. n^2 is O(n (log n)^2)

k. 2^n is O(2^2^n)

l. 3^n is (5^n)