In Exercises 1-3, determine whether the given set, together with the specified operations of addition and scalar multiplication, is a complex vector space. If it is not, list all of the axioms that fail to hold.
1. The set of all vectors in C2 of the form

With the usual vector addition and scalar multiplication
2. The set Mmn(C) of all m X n complex matrices, with the usual matrix addition and scalar multiplication
3. The set C2, with the usual vector addition but scalar multiplication defined by

ta tri c-c