The ratio of the output force of the hoist to the input force of the operator is known as
weight difference gear ratio dynamic fraction
mechanical advantage

I would go with d)Mechanical advantage!
x

Which of the following is an example of an opposing signal? no examplthates given.   i would say, that traffic lights in a city at major intersections direct the flow of traffic in opposite directions so would be an example.also, stop signs on either side of the same street would be an example. at a train crossing, the light for allowing car traffic in opposite directions or not would be another example.