I think it is (3) 690 N. You can use the theorem of Impulse and momentum where the impulse is equal to the change in momentum or:
[tex]F \Delta t=m v_{f}-m v_{i}[/tex] (where f is for final and i for initial).
So you get:
[tex]F*0.65=0-(75*6)[/tex]
[tex]F=692 N[/tex]