I think you value of applied force is incorrect, thus let use N=10-5 N
Kinetic Energy and the Work-Energy Principle statement is net work = change of kinetic energy, Wnet=∆KE.
Now, work done on the arrow is W=Fd=(0.75 m)(10-5 N)=7.5*104 J
That amount of energy will convert into change of kinetic energy, that is, mV2/2=7.5*104 J ( as initial V and KE was zero).
Now, you can calculate V=[(2*7.5*10-4 J)/(0.085 kg)]1/2=0.133 m/s