1. A train moving at 25 m/s is traveling towards Mr. Anderson, who is standing in the middle of the tracks. What frequency does Anderson hear if the train has a horn frequency of 1000 Hz?

i guess that visual aids present persuasive examples to what you are presenting, some factors would be theme (does it fit with the color, information, what you are presenting), size (can you see it, is it a big enough span of data/information), and overall look of the visual aid.

hope this : )

correct it is c.) b b

the answer is 12 as i may remember

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