Electromeric and Hyperconjugation Effects — Prelims Questions

Which of the following carbocations is the most stable?

Which of the following statements about the Electromeric effect is INCORRECT?

Which of the following alkenes is the most stable?

Which of the following effects is responsible for the ortho-para directing nature of alkyl groups in electrophilic aromatic substitution?

Identify the type of Electromeric effect involved in the reaction of an aldehyde with a nucleophile (e.g., $CN^-$).

How many $\alpha$-hydrogens are present in 2,2-dimethylpropane?