input question: What is the final step of the following process: - An airline reservation is made - The passenger arrives early at the airport - The luggage is checked - The passenger waits in line - The passenger shows their identification and gets a boarding pass - The passenger goes to their gate - The passenger gets in line when it's time to board - The person boards the plane - The plane arrives at the destination???
output answer: The passenger gets off the plane at their destination.

What is the final step of the following process: - One type of air pollution is the addition of carbon dioxide gas into the air - Some scientists believe that releasing too much carbon dioxide into the atmosphere is one of the causes of global warming - This upsets the balance of the carbon cycle - The ozone layer helps protect us from harmful rays from the sun - It is getting damaged from air pollution such as methane gas from livestock and CFCs from spray cans - Acid rain is created when gasses such as sulfur dioxide get high into the atmosphere - The wind can blow these gasses for miles and then they get washed out of the air when it rains
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Answer: This rain is called acid rain and can damage forests and kill fish.

Q: What is the final step of the following process: - The nuclei of some atoms have too few or too many neutrons - The atoms become unstable - The atoms split - In alpha decay, two protons and two neutrons are released from the atom - In beta decay, a neutron changes into a proton and an electron - The proton joins the nucleus of the atom
A: The electron is released

Question: What is the final step of the following process: - Coal is mined out of the ground - Coal is pulverized into fine powder - The coal is mixed with hot air - The coal and hot air are blown into a boiler - The coal and hot air burn over a fire - Highly purified water is pumped through pipes in the boiler - The water turns into steam - The steam presses against turbines - The turbines spin
Answer: Electricity is produced.

[Q]: What is the final step of the following process: - Greenhouse gases are released into the air by human activities - The earth changes energy from the sun into heat - Heat rises from the ground - Greenhouse gas molecules in the atmosphere prevent the heat from going into space - The temperature of the earth increases - The temperature continues to rise and melts the polar ice caps
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[A]: The temperature rises even faster.

Problem: Given the question: What is the final step of the following process: - Coal is loaded into the firebox - The boiler produces steam under high pressure - The steam generated in the boiler flows down into a cylinder - Just ahead of the wheels, pushing a tight-fitting plunger, the piston - The piston is connected to one or more of the locomotive's wheels through a kind of arm-elbow-shoulder joint called a crank and connecting rod - As the piston pushes, the crank and connecting rod turn the locomotive's wheels and power the train along
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The answer is:
An outlet valve opens and the piston pushes the steam back through the cylinder and out up the locomotive's chimney