Problem: Given the question: What is the missing first step of the following process: - The earth changes energy from the sun into heat - Heat rises from the ground - Greenhouse gas molecules in the atmosphere prevent the heat from going into space - The temperature of the earth increases - The temperature continues to rise and melts the polar ice caps - The temperature rises even faster.
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The answer is:
Greenhouse gases are released into the air by human activities

Problem: Given the question: What is the missing first step of the following process: - Air is transported to the lungs - Air reaches the alveoli, the smallest air sacs in the lungs - In the alveoli, air passes into the blood within small capillaries - The gaseous oxygen in the air dissolves into the capillary blood - The dissolved oxygen is picked-up by red blood cells - The red blood cells bind the oxygen via a protein called heme - Red blood cells circulate throughout the body and reach the various tissues - Within small capillaries, the heme release the oxygen - The oxygen can then reach the cells within the tissue -
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The answer is:
The human body takes a breath inward

Problem: Given the question: What is the missing first step of the following process: - The star does not have enough mass to become a neutron star - The star goes through a change in its core and bonds helium to carbon and oxygen - The star becomes a red giant - A mass of carbon and oxygen builds up in the center of the star - The star sheds its outside layers and becomes a nebula - The star leaves behind the core which becomes a dwarf star.
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The answer is:
A star forms