I cant figure this out

An electron with initial velocity vo = 1.52 x 10' m/s enters a region 1.00 cm long where it is electrically accelerated (see the figure). It emerges with velocity v = 5.65 x 10 m/s. What is its acceleration, assumed constant? (Such a process occurs in old television sets.) Nonaccelerating Accelerating region region L Path of electron Source of high voltage