It might have mold On The surface
Tight hydrogen bonding
The atoms in a compound are held together by a chemical bond. The chemical bonds can be either covalent bonds or ionic bonds. Both the bonds are considered very strong bonds. These bonds are mainly formed by sharing of electrons or in the case when one of the elements making the compound donates electron to the other element. The nucleus of each atom attracts to form a strong bond. This property of attraction between the nucleus of the atoms actually helps in forming the chemical bonds.<span>
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Answer:
B.Lubricating cartilage at joints
Acid precipitation is an agent of erosion weathering.
When you inhale and exhale, you actually breathe. When you inhale, your intercostal muscles between ribs and diaphragm contract. This increases the space in chest cavity so your lungs can expand and the air enters the lungs. When you exhale, intercostal muscles and diaphragm relax reducing the space in the chest which leads to removing the air from the lungs.