9. (9 points) For each of the following vector spaces U and V and functions T : U > V, determine Whether T is a linear transformation, and justify your answer. (a) U = MW\" (the space of n X n matrices), V = 7371, and T(A) is the characteristic polynomial of A. (b) U = R3, V = span{(1,2,3)}, T(u) = proj(1'2i3)(u). (c) U = R3, V = R3, T(u) = u x (1,2,3)