Rank of the following groups in order of $R, S$ precedence ($IV$ is highest) 

$\mathop { - CH{{(C{H_3})}_2}}\limits_1 \,\,\,\,\,\,\,\,\,\,\,\mathop { - C{H_2}C{H_2}Br}\limits_2 \,\,\,\,\,\,\,\,\,\,\mathop{ - C{H_2}Br}\limits_3 \,\,\,\,\,\,\,\,\,\mathop{ - C{{(C{H_3})}_3}}\limits_4$

$I  =  II  =  III  = IV$

A pair of stereoisomers might be classified in various ways. Which of the  following statement are true with respect to pairs of stereoisomers?

$(a)$ They might be configurational isomers  $(b)$ They might be diastereomers
$(c)$ They might be constitutional isomers    $(d)$ They might be tautomers
$(e)$ They might be conformational isomers   $(f)$ They might be enantiomers
$(g)$ They might be positional isomers

Of the following, the compound possessing optical isomerism

Disymmetric object is one which is

Total number of stereo isomers possible for the given structure:

$Image$

Which of following compound will rotate the plane polarized light at room temperature?