input question: What is the missing first step of the following process: - The blood is passed through the nephrons in the kidneys - The kidneys filter the waste from the blood - The clean blood is circulated out of the kidneys - Excess water and waste is expelled from the kidneys in the form of urine.???
output answer: The kidneys receive blood through the renal artery

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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Answer: The salt water is heated

Q: What is the missing first step of the following process: - Remove any ice cubes currently in the tray - Fill the tray with cold water - Ensure the tray is evenly filled to an appropriate level - Open the freezer - Place the tray in the freezer - Close the freezer door - Wait.
A: Get the ice tray

Question: What is the missing first step of the following process: - The pressure causes plates to move - Magma explodes to the surface - The lava from the eruption cools to form new crust - After several eruptions, the rock builds up and a volcano forms -
Answer: Magma rises through cracks in the Earth's crust

[Q]: What is the missing first step of the following process: - The matter forms on the sea floor - Layers of sediment form above the matter compressing it - After many years the matter is compressed and heated - The result is that crude oil forms.
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[A]: Living organisms in the sea die

Problem: Given the question: What is the missing first step of the following process: - The lungs expand - Air is pulled from outside the body, into the lungs - The membranes in the lungs collect oxygen molecules - Oxygen is transferred to red blood cells - Red blood cells distribute oxygen throughout the body -
++++++++++++++++++++++++++++++++
The answer is:
The diaphragm contracts