For #1, I'd say it's "It will usually bond to multiple atoms which can provide a total of 4 additional electrons."
2. Ionic (I'm quite certain because anions/cations (-1 & +1) are Ionic from what I recall, if that's true it's Ionic.
3. "comparison of the associated families to which the elements belong" and
"the difference in electronegativities" are what I would choose, as I mentioned in a comment earlier.
If I'm wrong let me know, but I am at least 80% sure that these responses are correct from what I remember in Chemistry.
Its B i believe, Storms and currents can bring in sediments from other places
If, in a peptide chain, there were 85 amino acids each joined by peptide bonds, there would only be 1 N-terminus group that would be present. The N-terminus group is always the start of the chain of a amino acid chain or a protein or a polypeptide. It refers to the free amine group present that is located at the end part of the chain. So, that no matter how many amino acids in a chain there would always be only one N-terminus group.
