Which of the following statements are correct? (Alkyl groups reduce acidity by +I effect and hyperconjugation.)

The methyl group of p-toluic acid donates electrons and destabilises the carboxylate, so benzoic acid is stronger. Formic acid (pKa 3.75) has no donor alkyl group, unlike acetic acid (4.76). The p-nitro group stabilises the carboxylate. In p-cresol the methyl destabilises the phenoxide, so p-cresol is a weaker acid than phenol and statement 4 is false.