Given the following, what is the net force on the particle? What is the acceleration of the particle? How long will it take to strike one of the plates?

A particle with a charge of #-4.00 x 10^-6 C# moves through a uniform electric field of #70.0 N/C# directed downwards. It is moving horizontally at #12.0 cm/s# exactly between two plates that are #10.0 cm# apart. The particle has a mass of #0.0400 g#.