Answer:
The first line of defense involves skin.
Answer:
Chemical bonds contain potential energy.
Explanation:
Chemical bonds always contain potential energy. The atoms of the bond want to move to a lower energy to become more stable.. The energy for breaking bonds only comes when stronger bonds are formed. This energy is used to tear apart the bonds holding the Hydrogen atoms together. The strength of the covalent bonds depend on the overlap between the valence orbitals of the bonded Atom.
XX Chromosome and Male have XY chromosome.
Answer:
The moon is earths only permanent natural satellite
the moon always shows earth the same face
the sun and moon are not the exact size
the moon is 238,900 miles from earth
the moon is estimated to be about 4.6 billion years old