Evaluate: 623×3√673√66
We have
623×3√673√66
=623×673663 [∵am×an=a(m+n), √a=a1a,am÷bn=am−n]
=6(23+73−63)
=6(33)
=61
The colour of 62Sm3+ is yellow. What is the colour of 66Dy3+?