In each of the following questions, select the related word/letters/number from the given alternatives.
Demographer : People :: Philatelist : ?
RIAHC : CHAIR :: OGNAM : ?
PNS : OOT : DBH : ?
91 : ? :: 64 : 54
$$\frac{2}{3}:\frac{19}{29}::\frac{8}{7}:?$$
Sepal : Flower ::
In each of the following questions, find the odd number/letters/number pair from the given alternatives.