4*22 - 3*2 = 16 - 6 = 10
6b4 / 5c4d4 / 3ab2 / 20c3d Division is not associative and since there are no brackets (parentheses) the operations are evaluated from left to right. Thus 6b4 / 5c4d4 = 6/5*b4c-4d-4 6b4 / 5c4d4 / 3ab2 = 6/5*b4c-4d-4/ 3ab2 = 2/5*a-1b2c-4d-4 6b4 / 5c4d4 / 3ab2 / 20c3d = 2/5*a-1b2c-4d-4/ 20c3d = 1/50*a-1b2c-7d-5 or b2/(50ac7d5)
4d2+16 4(d2+4)
That's 4d2 .
1234 = 4d2
4d (d + 5)
(2d-7)2
[Kr] 5s2 4d2
It is [Kr] 4d2 5s2
[Kr] 5s2 4d2
Zirconium, Zr
Zirconium - but it could be simplified to [Kr] 4d2 5s2