input: Please answer the following: What is the missing first step of the following process: - The oxygen travels into the lungs - The oxygen binds to hemoglobin proteins within erythrocytes (red blood cells) - The erythrocytes are pumped through the body by the heart - All cells receive the oxygen.
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output: Oxygen enters the body through the mouth or nose

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

input: Please answer the following: What is the missing first step of the following process: - The virus attaches to the cell's surface - The cell swallows the virus - The virus' RNA is released into the cell - The cell mistakenly reads the virus' RNA instead of its own - The cell creates new viruses - The animal cell releases the new viruses - The new viruses can infect more cells.
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output: The virus finds an animal cell

input: Please answer the following: What is the missing first step of the following process: - As the saltwater is heated the water becomes a gas - The salt particles sink to the bottom of the container - Gaseous water is piped into another container - Allowed to cool - The salt particles are left behind in the first container - The second container contains fresh water.
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output:
The salt water is heated