The electrons that produce the picture in a TV set are accelerated by a very large electric force as they pass through a small region in the neck of the picture tube. This region is 1.7 cm in length, and the electrons enter with a speed of 1 × 10^5 m/s and leave with a speed of 2.5 × 10 ^6 m/s. How long is the electron in the accelerating region? Answer in units of s.