A programmer plans to develop a new software system. In planning for the operating system that he will use, he needs to estimate the percentage of computers that use a new operating system. How many computers must be surveyed in order to be % confident that his estimate is in error by no more than percentage point.

24 would be the answer

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.

One of the angles would be 70 degrees and the other one would be 90 degrees