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In this paragraph...name a supporting sentence.
One of the challenges that is unique to space is the fact that space is a vacuum, which is a risk for various reasons. First, in a vacuum there is no atmosphere and therefore no air pressure. Without air pressure, the human body has no oxygen to sustain itself. After too many minutes without oxygen, a person would lose consciousness and eventually die. Also, in a vacuum a person's blood will gradually begin to boil. Finally, without an atmosphere, the rays of the Sun can cause radiation poisoning.
What is "First, in a vacuum there is no atmosphere and therefore no air pressure."
"Without air pressure, the human body has no oxygen to sustain itself."
"After too many minutes without oxygen, a person would lose consciousness and eventually die."
"Also, in a vacuum a person's blood will gradually begin to boil."
"Finally, without an atmosphere, the rays of the Sun can cause radiation poisoning."