input: Please answer the following: What is the missing first step of the following process:  -  The lungs remove oxygen from the air - Oxygen diffuses from alveoli in the lungs to the bloodstream - Hemoglobin in red blood cells attaches to the oxygen - Red blood cells carry oxygen all around the body - Oxygen diffuses into cells from capillaries.
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output: Air goes into the lungs

Please answer this: What is the missing first step of the following process:  -  The bird collects bits of sticks and grass - The sticks and grasses are placed between support branches - Leaves, mud and spider webs are added to the sticks - The mud, leaves and webs glue the sticks together - The solid nest supports the eggs -
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Answer: A bird picks a spot high spot, often in a tree

Problem: What is the missing first step of the following process:  -  The spores fall to the ground - The spores germinate - The spores begin to grow mycelium - The mycelium begin to sprout a bud - A new mushroom is formed.

A: Spores are dispersed into the air by a mature mushroom

Problem: Given the question: What is the missing first step of the following process:  -  The liver produces bile - The liver produces proteins for blood plasma - The liver converts excess glucose into glycogen for storage - The liver converts ammonia to urea - The liver regulates blood clotting.
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The answer is:
The liver filters blood from the digestive tract

input question: What is the missing first step of the following process:  -  Water droplets are in clouds - The air gets cold - Water droplets turn into ice crystals - Ice crystals in clouds stick together and become snowflakes.???
output answer: Water evaporates from the ground up to the sky

input 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 -???
output answer:
A machine called a pulverizer grinds the coal into a fine powder