Problem: - Wind and water erode rocks - The wind and water pick up sediment that came off the rocks - Sediment is carried to an area by the wind, water, air, or ice - Sediment is deposited on the same spot many times - The sediment piles on top of other sediment for a long time - The sediment near the bottom is compressed by the weight of newer sediment What might be the last step of the process?

A: The sediment becomes sedimentary rock as it is pushed together by the heavy weight

Problem: - People breathe and expel carbon dioxide - Engines produce carbon dioxide - Living things produce waste - Waste decomposes - Decomposition produces methane - Water evaporates - Water vapor joins the atmosphere What might be the last step of the process?

A: Carbon dioxide, water vapor and methane are greenhouse gases

Problem: - Fuel mixes with air - Mix gets inducted into cylinder - Piston compresses the mix - Spark plug emits a spark that ignites it causing combustion - Combustion gases expand - Pushes piston during power stroke What might be the last step of the process?

A: Exhaust valve opens to vent exhaust out tail pipe.

Problem: - Warm weather causes water to evaporate - The water rises up in the air - It starts to cools down - The water starts to condense - It forms into clouds What might be the last step of the process?

A:
When there is enough moisture in the clouds it starts to rain.