Optical activity of an enantiomeric mixture is $+12.6^{\circ}$ and the specific rotation of $(t)$ isomer is $+30^{\circ}$. The optical purity is $........\%$
$41$
$43$
$44$
$42$
Total number of possible stereoisomers of dimethyl cyclopentane is ....
Which of the following pairs of compounds is a pair of enantiomers ?
Which of the following molecules are chiral ?
Relation between $(A)$ and $(B)$ is
Which of the following is optically active