The substituents `R_(1) and R_(2)` for nine peptides are listed in the table given below. How many of these peptides are positively charged at pH = 7.0 ? `{:(H_(3)N-CH-CO-NH-CH-CO-NH-CH-CO-NH-CH-COO),(" | | | |"),(" "H" "R_(1)" "R_(2)" H"):}` `{:("Peptide","R"_(1),"R"_(2)),("I","H","H"),("II","H","CH"_(3)),("III","CH"_(2)"COOH","H"),("IV","CH"_(2)"CONH"_(2),("CH"_(2))_(4)"NH"_(2)),("VI",("CH"_(2))_(4)"NH"_(2),("CH"_(2))_(4)"NH"_(2)),("VII","CH"_(2)"COOH","CH"_(2)"CONH"_(2)),("VIII","CH"_(2)"OH",("CH"_(2))_(4)"NH"_(2)),("IX",("CH"_(2))_(4)"NH"_(2),"CH"_(3)):}`

The substituents `R_(1) and R_(2)` for nine peptides are listed in the

1.	The substituents `R_(1) and R_(2)` for nine peptides are listed in the table given below. How many of these peptides are positively charged at pH = 7.0 ? `{:(H_(3)N-CH-CO-NH-CH-CO-NH-CH-CO-NH-CH-COO),(" \| \| \| \|"),(" "H" "R_(1)" "R_(2)" H"):}` `{:("Peptide","R"_(1),"R"_(2)),("I","H","H"),("II","H","CH"_(3)),("III","CH"_(2)"COOH","H"),("IV","CH"_(2)"CONH"_(2),("CH"_(2))_(4)"NH"_(2)),("VI",("CH"_(2))_(4)"NH"_(2),("CH"_(2))_(4)"NH"_(2)),("VII","CH"_(2)"COOH","CH"_(2)"CONH"_(2)),("VIII","CH"_(2)"OH",("CH"_(2))_(4)"NH"_(2)),("IX",("CH"_(2))_(4)"NH"_(2),"CH"_(3)):}`
Answer» Correct Answer - 4