Show that:

A) A is similar to A.

B) If B is similar to A, then A is similar to B.

C) If A is similar to B and B is similar to C, then A is similar to C.

I dont know how to do the theoretical problems in my book. I know that similar means:

A matrix B is said to be similar to a matrix A if there is a nonsingular matrix P such that

B = P^-1 A P