Blood carries oxygen to the cells throughout your body to keep them healthy. Explanation:
Hypoxemia can cause mild problems such as headaches and shortness of breath. In severe cases, it can interfere with heart and brain function. Hypoxemia that causes low oxygen levels in your body's tissues is called hypoxia.
Brain cells are very sensitive to a lack of oxygen. Some brain cells start dying less than 5 minutes after their oxygen supply disappears. As a result, brain hypoxia can rapidly cause severe brain damage or death.
Explanation:
Other symptoms can include: hallucinations and delusions; increased agitation and confusion; depression and other mood disorders; personality changes, such as irritability and a reduced threshold for frustration; and an inability to focus or concentrate.
The sentence that is true is A galaxies are holder together by gravity it is not D because galaxies are real its not C because they are not being pulled apart and its not B because galaxies are held together.