Arsenal Summer Transfer Needs !

Arsenal had an up and down campaign last term. Arsenal early on in the season sat down at 17^th place in the table and finished 3^rd with a wide margin separating them and the Manchester clubs. With some new additions, Arsenal could be fighting for a Premier League Trophy. Here are the key needs as I see them.
-Back-up Right Back
-Back-up Right Back
-Defensive Midfielder 
-Another Striker