310.
2000
20 of them.
39
To get the 2s complement, find the 1s complement (by inverting the bits) and add 1. Assuming that number is [4-bit] binary it would be 1000. If it is preceded by 0s, as in, for example, 0000 1000, then it would be 1111 1000.
300 sir
There is only one 2s orbital in an atom.
25 of them
310.
2000
100 2s for the hundreds digit of 200-30010 2s for the tens digit of 220-23010 2s for the ones digit of 200-300________________________________120 '2s'
unknown
1
36
26
42
20 of them.