Using a winch with 2 running blocks and 2 fixed blocks to bring a 200-kg- object to the height of 2 meters with the traction of 625N and an 8-meter distance must be pulled. The efficiency of the winch is.......?

Using a winch with 2 running blocks and 2 fixed blocks to bring a 200-kg- object to the height of 2 meters with the traction of 625N and an 8-meter distance must be pulled.The efficiency of the winch is.......?
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