How can you explain a sediment deposit that contains unlayered and randomly sorted material at the bottom and layered, well-sorted material at the top? PLEASE HEL !

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.

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