If all the letters of the world $\displaystyle \bf{\mathbb{INDONESIA}}$ are arrange in a English Dictonary, Then

$\displaystyle (a)\;\; $ Rank of The word $\displaystyle \bf{\mathbb{INDONESIA}}$

$\displaystyle (b)\;\; 61^{th}$ Letter in Dictonary araanging $\displaystyle \bf{\mathbb{INDONESIA}}$