In a matroid M = {E, I}, where E is the ground set and I the independent sets, a circuit C is a minimal dependant subset of E, i.e. a subset of elements of E such that removal of any element from C leaves an independent set. (a) What are the circuits of the matric matroid. (b) Show that if C1 and C2 are circuits and C1 C2 then C1 = C2