Which of the following alkenes does $\underline{NOT}$ exhibit cis-trans isomerism?

Which products are obtained on reaction of but$-1-$ene with $HBr$ in the presence of peroxide?

Addition of $OsO_4$ to cyclopentene would give a product which is

Identify the major product $B$ in the given sequence of reactions:
$CH_3-C \equiv CH$ $\xrightarrow{H_2 / Pd-C} A$ $\xrightarrow{(C_6H_5CO)_2O_2 / HBr} B$

Which reaction is known as Kharash reaction?

An alkene $X$ $(C_4H_8)$ exhibits geometrical isomerism. Oxidation of $X$ with $KMnO_4 | H^+$ gives $Y$. On heating the sodium salt of $Y$ with a mixture of $NaOH$ and $CaO$,$Z$ is obtained. What is $Z$?