Sebastian says, "All rhombuses have 2 acute angles and 2 obtuse angles." Which of the following would be a valid counterexample to prove that his conjecture is false?
1) A square is a rhombus, and it has 4 right angles.
2) A rectangle is a rhombus, and it has 4 right angles.
3) A rhombus does not always have 2 acute angles and 2 obtuse angles.
4) A rhombus has 4 congruent sides, so it doesn't have to have acute angles.
