Answer:
pI = 6.16
Explanation:
The pI is given by the average of the pKas that are involved. In this case,
Pka of carboxylic acid was given as 2.72 and that of the Amino group was given as 9.60. the average would then be ½(2.72+9.60)
= 6.16
The largest atomic radius has Ba,because they are all metals of 2nd group,but as you know when you go down upright in the periodic table the metallic features getting stronger but also orbital layers increasing,and you can say more layers larger atomic radius.Hope I helped,sorry for English
