What is the final step of the following process: - Air enters the nose or mouth and travels through the windpipe into the lungs - The lungs have a series of smaller and finer tubes and sacs - Air reaches the smallest and finest air sacs called alveoli - Oxygen travels from the alveoli into the blood - Oxygen-rich blood is carried to the heart - Oxygen-rich blood is pumped throughout the body by the heart - Cells take in the oxygen rich blood and release carbon dioxide rich blood - The carbon dioxide rich blood travels to the lungs
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Answer: Carbon dioxide travels through the throat and is exhaled.

Q: What is the final step of the following process: - Minerals fill spaces between bits of sediment - The sediments become glued together - The glued together parts become hard like cement - The sediment becomes a big rock - The rocks erode slowly - The rocks come apart - The rocks become smaller rocks - The rocks continue to erode into smaller rocks
A: The process starts again.

Question: What is the final step of the following process: - Food is taken into the mouth - The food is chewed - Saliva mixes with the food and starts breaking it down - The chewed food travels down the esophagus to the stomach - The stomach secretes acid - Grinds and mixes the food - The food moves to the small intestine - The small intestine uses enzymes to further break down the food - The food passes into the colon
Answer: The food is expelled from the body.

[Q]: What is the final step of the following process: - The thermostat senses that the temperature has dropped - A signal is sent to the heating system - Heating oil travels from the tank to the burner - The oil becomes a fine mist mixed with air - The oil/air combination is injected into the burner - The burner is ignited in the combustion chamber - The furnace heats the air - The blower sends the heated air through the ducts
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[A]: The heated air comes out the vents and into the room.

input: Please answer the following: What is the final step of the following process: - When water freezes it becomes 10% bigger, or takes up 10% more space - As water expands it puts great pressure on the walls of anything containing it, including any rocks which happen to be surrounding it - The force of the pressure exerted on the rock surrounding it is enough to wedge the walls of the crack farther apart, thus expanding and deepening the crack - Clay expends when wet like ice does - This causes rock to break apart - Some plants like mosses and lichens are capable of growing without soil on bare rock
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output: When they do this their roots penetrate pores and crevices and cause rocks to split apart as the roots force their way down through the rocks

What is the final step of the following process: - Limestone is located under the soil - Rain picks up carbon dioxide as it falls to earth - The rain falls on the soil over the limestone - The carbon dioxide in the rain washes through the soil - The carbon dioxide turns into acid - The acid in the rain gets to the limestone below the soil - The acid dissolves the limestone - Acid continues to erode the limestone with more rain over time
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Answer:
The eroded limestone sometimes forms caves.