Q: What is the missing first step of the following process: - Engines produce carbon dioxide - Living things produce waste - Waste decomposes - Decomposition produces methane - Water evaporates - Water vapor joins the atmosphere - Carbon dioxide, water vapor and methane are greenhouse gases -
A: People breathe and expel carbon dioxide

Question: What is the missing first step of the following process: - 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 - The temperature rises even faster.
Answer: Greenhouse gases are released into the air by human activities

[Q]: What is the missing first step of the following process: - Is exposed to air - A chemical reaction occurs - The iron starts to oxidize - The iron starts to rust.
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[A]: Iron is exposed to oxygen

input: Please answer the following: What is the missing first step of the following process: - The sperm implants itself into the egg - The sperm and egg form a zygote on the wall of the uterus - The fetus grows and develops - The woman gives birth to a baby - The baby is raised by parents until it is able to take care of itself - The person goes out into the world and finds a job - The person meets other people and has a life - The person gets a career, and gets married - The person retires and eventually passes away -
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output: A sperm meets an egg in the uterus of a woman

Please answer this: What is the missing first step of the following process: - Over long periods of time rain can hit the limestone - And cause a acidic reaction - The limestone will slowly disintegrate - A large gap with be where the limestone was - Result in the cave.
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Answer: Some of the rock in the ground is made of limestone

Question: What is the missing first step of the following process: - The coal powder mixes with hot air, which helps the coal burn more efficiently, and the mixture moves to the furnace - The burning coal heats water in a boiler, creating steam - Steam released from the boiler powers an engine called a turbine, transforming heat energy from burning coal into mechanical energy that spins the turbine engine - The spinning turbine is used to power a generator, a machine that turns mechanical energy into electric energy - This happens when magnets inside a copper coil in the generator spin - A condenser cools the steam moving through the turbine - As the steam is condensed, it turns back into water - The water returns to the boiler, and the cycle begins again -
Answer:
A machine called a pulverizer grinds the coal into a fine powder