A lamp is 3 metres high on a post located 5 metres from a vertical wall. A 2 metre tall man walks toward the wall from the lamppost on a path perpendicular to the wall. He is walking at a rate of 1 metre per second. When he is 1 metre from the wall, how fast is the shadow of his head moving up the wall?
◦ 0.36 metres per second
◦ 0.96 metres per second
◦ 1.29 metres per second
◦ 0.52 metres per second
◦ 0.31 metres per second