Why do we use helium in balloons instead of hydrogen.

Why does a plastic bottle that is sealed at a high altitude change it’s shape when taken to lower altitude

Convert .347 kilometers to miles show your work

#7 how does the structure of amino acids allow them to form a polypeptide? each amino acid has an amino group and a carboxyl group. each amino acid has a hydrogen atom and a carboxyl group. each amino acid has a carboxyl group and an r group. each amino acid has an r group and a hydrogen atom.