1. A square matrix all of whose elements except the main diagonal are zeros is called a :

(a) null matrix

(b) singular matrix

(c) diagonal matrix

(d) symmetric matrix

2. Square matrix A for which A^{T} = -A is called a :

(a) row matrix

(b) column matrix

(c) symmetric matrix

(d) skew-symmetric matrix

3. Square matrix A for which A^{T} = A is called a :

(a) row matrix

(b) column matrix

(c) symmetric matrix

(d) skew-symmetric matrix

4. A square matrix A with complex entries for which (A)^{T }= –A is called :

(a) identity matrix

(b) hermitian matrix

(c) symmetric matrix

(d) skew-hermitian matrix

5. This matrix is a _______ .

(a) null matrix

(b) row matrix

(c) square matrix

(d) symmetric matrix