How many paths of longest length are there in each of the folio wing graphs? (Remember that a path such as v1 → v2 → v3 → is considered to be the same as the path v3 → v2 → v1.)
(a) K1.4
(b) K3,7
(c) K7,12
d) Km,n where m, n ∈ Z+ with m < n.