Identify the relationship between the following two compounds: $C_6H_5COOH$ and $o-HOC_6H_4CHO$.

How are the following compounds related?

The compound which shows metamerism is:

Identify the pairs of compounds that represent position isomerism.
$(I)$ $CH_3-CH_2-CH_2-CH_2-OH$
$(II)$ $CH_3-CH_2-CH(OH)-CH_3$
$(III)$ $CH_3-C(OH)(CH_3)-CH_3$
$(IV)$ $CH_3-CH(CH_3)-CH_2-OH$
$(V)$ $CH_3-CH_2-O-CH_2-CH_3$
$(VI)$ $CH_3-O-CH_2-CH_2-CH_3$
$(VII)$ $CH_3-O-CH(CH_3)-CH_3$

Which of the following is not a functional isomer of the others?

Which of the following compounds will exhibit metamerism?