Consider an ink jet printer, the basic mechanism is that drops of ink, each with a radius of r=20um, are charged to q=1.3E10-13C and sprayed from a nozzle towards the page at an initial speed of 20 m/s. On the way to the paper, they pass a region with a uniform electric field of magnitude E between two charges plates which deflects them up or down, Assume that the distance from the center of the plates to the paper is d= 2cm. The maximum height of a letter is 6mm, i.e. the drops have to be deflected up or down 3 mm. What is the max electric field strength needed?