If A is a matrix of order m × 3, B is a matrix of order 3 × 2 and R is a matrix of order 5 × n such that AB = R, the values of m and n are :

1. m = -5 and n = -2

2. m = 5 and n = 2

3. m = 5 and n = -2

4. m = 2 and n = 5

A, B and C are three matrices each of order 5; the order of matrix CA + B² is :

1. 5 × 4

2. 5 × 5

3. 4 × 5

4. 5 × 3