A velocity selector has an electric field of magnitude 2670 N/C, directed vertically upward, and a horizontal magnetic field that is directed south. Charged particles, traveling east at a speed of 6.00 x 103 m/s, enter the velocity selector and are able to pass completely through without being deflected. When a different particle with an electric charge of +4.10 x 10-12 C enters the velocity selector traveling east, the net force (due to the electric and magnetic fields) acting on it is 1.65 x 10-9 N, pointing directly upward. What is the speed of this particle?