Which of the following statements about the borax bead test are correct?

1. AA bead of $\mathrm{Cu}{}^{2+}$ is green when hot and blue when cold in the oxidising flame.
2. B$\mathrm{Cr}{}^{3+}$ gives a green bead in both the oxidising and the reducing flames.
3. C$\mathrm{Mn}{}^{2+}$ gives an amethyst bead in the oxidising flame that becomes colourless in the reducing flame.
4. D$\mathrm{Fe}{}^{3+}$ gives a bottle-green bead in the oxidising flame and a yellow bead in the reducing flame.