(a) Which one of the following three amines can be prepared by either the Gabriel synthesis or the Staudinger reaction: 2,2-dimethyl-1-propanamine, 3-methyl-1-pentanamine, or N-butylaniline?

(b) Starting with an alkyl halide, propose a synthesis for the compound you chose in part (a), using the Gabriel synthesis.

(c) Propose an alternative synthesis for the same compound using the Staudinger reaction and the same alkyl halide starting material.

(d) Explain why the other two amines cannot be prepared by either method.