Which of the following best describes the flow of electrons in the acid-catalyed dimerizantion of `(CH_(3))_(2)C=CH_(2)`?

Which of the following best describes the flow of electrons in the acid-catalyzed dimerization of (CH_3)_2C = CH_2 ?

Which of the following best describes the nucleophilic addition step in the acid-catalyzed hydrolysis of acetonitrile (CH_(3)CN) ?

Which of the following best describes the nucleophilic addition step in the acid catalyzed hydrolysis of acentonitrile (CH_(3)CN) ?

Which of the following procedures would be best for preparing isobutylisopropylamine, (CH_(3))_(2)CHNHCH_(2)CH(CH_(3))_(2) ?

Which of the following procedures would be best for prparing dimrthycyclohexylamine , C_(6)H_(11)N(CH_(3))_(2) ?

Which of the following is the best electron releasing group when present on Benzene ring (A) \(CH_{3}\) (B) \(CH_{3}-CH_{2}\) (C) \(CH_{3})_{2}CH-\) (D) \(CH_{3})_{3}C-\)