Problem: What is the missing first step of the following process:  -  The virus enters the human or animal body - The virus goes to the part of the body that contains its food - The virus consumes part of the body or materials that the body uses - The virus replicates and spreads - The virus causes symptoms in the body as the immune system tries to expel the virus.

A: Contact is made with a virus

Problem: Given the question: What is the missing first step of the following process:  -  Air goes through all the little branches in your lungs to fill up the air sacs, or alveoli - Oxygen goes through the walls of the alveoli and into the capillaries - The oxygen goes into the bloodstream - Oxygen is left and carbon dioxide is picked up - You breathe it out through your lungs -
++++++++++++++++++++++++++++++++
The answer is:
You breathe in

input question: What is the missing first step of the following process:  -  Coal is pulverized into fine powder - The coal is mixed with hot air - The coal and hot air are blown into a boiler - The coal and hot air burn over a fire - Highly purified water is pumped through pipes in the boiler - The water turns into steam - The steam presses against turbines - The turbines spin - Electricity is produced.???
output answer: Coal is mined out of the ground

What is the missing first step of the following process:  -  Magma crystalizes - Lava cools on the surface - Lava crystalizes - Minerals dissolved in water crystlize.
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Answer: Magma cools inside the crust

Q: 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 -
A: A sperm meets an egg in the uterus of a woman

[Q]: What is the missing first step of the following process:  -  As water expands it puts great pressure on the walls of anything containing it, including any rocks which happen to be surrounding it - The force of the pressure exerted on the rock surrounding it is enough to wedge the walls of the crack farther apart, thus expanding and deepening the crack - Clay expends when wet like ice does - This causes rock to break apart - Some plants like mosses and lichens are capable of growing without soil on bare rock - When they do this their roots penetrate pores and crevices and cause rocks to split apart as the roots force their way down through the rocks -
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[A]:
When water freezes it becomes 10% bigger, or takes up 10% more space