Acetone is formed by the ozonolysis of which of the following?

Suppose the following reaction sequence: $CH \equiv CH$ $\xrightarrow[\text{excess}]{NaNH_2 / \text{liq. } NH_3} A$ $\xrightarrow{2 CH_3 - I} B$ $\xrightarrow{H_2 / Pd - BaSO_4, \text{ quinoline}} C$ and $C$ $\xrightarrow{H_2 / Pd - BaSO_4, \text{ quinoline}}$ $\xrightarrow{NaNH_2 / \text{liq. } NH_3} D$. How are $C$ and $D$ related?

An alkene $X$ $(C_6H_{12})$ on ozonolysis gives acetaldehyde and ethyl methyl ketone. What is the product formed when $X$ reacts with $HBr$?

Write the structures and $IUPAC$ names of the different structural isomers of alkenes corresponding to the molecular formula $C_5H_{10}$. How many such isomers are possible?

$CH_3-CH(CH_3)-CH=CH_2 + HBr \to X$ (major product). $X$ is:

Find the major product for the reaction shown below.