Answer:-

• Presence of an alkyl group exerts an electron-releasing inductive effect (+I effect), stabilizing the positive charge on the bonded atom.
• The conjugate acid of ammonia is NH₄⁺, while that of 1° amine is RNH₃⁺.
• Due to the alkyl group, RNH₃⁺ is more stable compared to NH₄⁺.
• Primary aliphatic amines are consequently stronger bases than ammonia.