[Q]: What is the missing first step of the following process: - 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 - An outlet valve opens and the piston pushes the steam back through the cylinder and out up the locomotive's chimney -
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[A]: Coal is loaded into the firebox

[Q]: What is the missing first step of the following process: - Ice inside the cloud bumps around and causes electrostatic charges - The cloud becomes a thundercloud - Electrostatic energy builds and forms a strong negative charge - Positive energy is attracted to the negative energy in the cloud - This positive energy gathers on the ground - The positive energy connects with the negative energy and forms lightning.
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[A]: Ice forms inside a cloud

[Q]: What is the missing first step of the following process: - 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 - Exhaust valve opens to vent exhaust out tail pipe.
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[A]: Fuel mixes with air

[Q]: What is the missing first step of the following process: - The trees and plants burn - The animals lose their homes - If the animals can not escape, they may die from smoke inhalation - The plants that provide food are gone - The animals have little to eat -
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[A]:
A forest fire starts