In a borax bead test under hot condition, a metal salt (one from the given) is heated at point B of the flame, resulted in green colour salt bead. The spin-only magnetic moment value of the salt is __________ \( \text{BM} \) (Nearest integer) [Given atomic number of Cu = \( 29 \), Ni = \( 28 \), Mn = \( 25 \), Fe = \( 26 \)].
