To the nearest hundredth of a unit, what is the net charge of the peptide GLACIDR at pH 4.6? Use the following set of pKa values:

Group pKa N-ter 8.0 C-ter 3.1 Asp or Glu 4.0 Lys 10.5 Arg 12.4 His 6.0 Tyr 10.5 Cys 8.4

Also, use the approximation that if the separation between the pH and pKa of a group in question is 2 units or greater, then consider the group completely protonated or unprotonated as the case might be. (answer is 0.23 but unsure how)