[Q]: What is the missing first step of the following process: - Your thermostat sends a signal to your heating system to provide heat for your home - When your oil burner is engaged, heating oil travels from the tank to the burner by way of a pump - Here the oil becomes a fine mist mixed with air - The fuel/air mixture is then injected into the burner where it is ignited in the combustion chamber - The warm air is disbursed through vents, hot water through baseboards, or by steam radiators -
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[A]: Your thermostat senses that the room temperature has fallen below your thermostat setting

input: Please answer the following: What is the missing first step of the following process: - Waste enters the kidneys - A processing moment in the kidneys let waste and fluid pass - Prevents larger molecules to pass - Fluid goes back to the bloodstream - Bad waste is removed - The final product is turned into urine.
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output: Fluid

Please answer this: What is the missing first step of the following process: - They sit still on a perch, like a stump of branch, and wait for prey - They use their highly sensitive hearing to locate prey that cannot be seen - They use their very keen vision to see prey in the dark - They fly silently, without flapping their wings, in order to surprise the prey - The owl silently glides or drops on its prey, grabbing it with its talons and beak - The owl eats the prey, or carries it back to its perch -
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Answer: Owls hunt around their hunting territory away from where they roost during the day

Problem: What is the missing first step of the following process: - The isotope is unstable - The isotope emits radiation - The isotope decays - The isotope loses some atomic particles - The isotope turns into a different element - The isotope is finished decaying and emitting radiation.

A: An isotope has too many protons

Problem: Given the question: What is the missing first step of the following process: - The can is taken to a recycling center - Melted down along with other cans - The melted metal is turned into bars - Becomes material for other products.
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The answer is:
A can is thrown away into a recycling bin

Problem: What is the missing first step of the following process: - After a rain, water seeps into cracks and pores of soil and rock - The water percolates beneath the land surface - Some of the water reaches a zone where all the cracks and pores in the rock are already filled with water - Rainwater absorbs some carbon dioxide as it passes through the atmosphere and even more as it drains through soil and decaying vegetation - The water combines chemically with the carbon dioxide - A weak carbonic acid solution is formed - This acid slowly dissolves calcite, forms solution cavities, and excavates passageways -

A:
Solution caves are formed in limestone and similar rocks by the action of water