Which of the following statements are true?

Let G₁ and G₂ be finite groups such that their orders |G₁| and |G₂| are coprime. Then any homomorphism from G₁ to G₂ is trivial.

Let G be a finite group. Let f : G → G be a group homomorphism such that f fixes more than half of the elements of G. Then f(x) = x for all x ∈ G.

Let G be a finite group having exactly 3 subgroups. Then G is of order p² for some prime p.

Any finite abelian group G has at least d(|G|) subgroups in G, where d(m) denotes the number of positive divisors of m.