several motorboats with the same mass are used in an experiment. the forces of the different motors versus their accelerations are graphed. what is the y-intercept of this graph?

It’s according to the question. but most of the time the answer is b

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.