Let A be a 4 3 matrix. Find the elementary matrix E that, as a premultiplier

Question:

Let A be a 4 × 3 matrix. Find the elementary matrix E that, as a premultiplier of A-that is, as EA-performs the following elementary row operations on A:
(a) Multiplies the second row of A by (- 2).
(b) Adds 3 times the third row of A to the fourth row of A.
(c) Interchanges the first and third rows of A.