76. The level of muddy water will decrease slightly if the model is left in a sunny location for several days because of Evaporation. The sun will vaporize the water found in the mud, turning it into it's gaseous state, which will then cause it to rise up and get stuck on the plastic wrap.
77. Precipitation
78.The reason that the sediment in the muddy water will remain the same is because the Mud will never evaporate like the water will, and therefore it will remain at the bottom of the container.
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