3.Supposetherulesforassigningquantumnumberswereasfollows: n=1,2,3,… l=0,1,2,…,n m=0,1,2,…,l＋1 s=＋or－Statethevaluesofl,m,sfortheelectronswhenn=1andn=2.Givetheelectronconfigurationforanatomwithtwelveelectrons.