For which sequence, decide whether there exists the bipartite graph with these degrees. If so, find out one. If not, discuss why.
a) ( 6, 6, 4, 4, 4, 4, 4, 4, 2, 2, 2)
b) (4, 4, 4, 4, 4, 3, 3, 2, 2)
c) (5, 5, 5, 5, 5, 5, 4, 4, 4)
d) (5, 4, 4, 3, 3, 2, 2, 2, 1)
e) (5, 5, 4, 3, 3, 3, 3, 3, 3)
f) (5, 5, 5, 5, 4, 4, 4, 3, 3)