PLEASE HELP If the momentum of a 60 kg sprinter changes from 400 kg m/s to 200 kg m/s,
how does her velocity change?

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 : )

im guessing the west of station b