A set of traffic lights hangs from the end of a metal cable. A horizontal chain pulls the traffic
lights to the right so that they are above the middle of the road. Fig. 1.1 shows the metal
cable inclined to the vertical.
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![A set of traffic lights hangs from the end of a metal cable A horizontal chain pulls the trafficlights to the right so that they are above the middle of the roa class=](https://us-static.z-dn.net/files/d3c/e233cd4d2a160cff99215f65c884928c.jpg)