(i)[2]
the $A$ letters are all adjacent,
(ii)[3]
the arrangement starts with a consonant ($T, N, Z$), the second position is a vowel ($A, I$), the third is a consonant, the fourth is a vowel, and the pattern continues alternately.
(iii)[2]
$4$ of the $8$ letters in TANZANIA are chosen. How many different selections include exactly $1$ $N$ and $1$ $A$?
(iv)[3]
$4$ of the $8$ letters in TANZANIA are chosen. How many different selections include exactly $1$ $N$?