The answer is the first one because the sodium is the first element of the third row, thus 3s^1
There are two ways to represent the chemical formula of a substance: in condensed form or in structural form. Ethane is an alkane which consist of two carbon atoms. Since the general formula for ethane is CₓH₂ₓ₊₂, the condensed formula is C₂H₆. The structural formula or the line-bond structure is shown in the attached picture.
1. <span>Count Sergei Lvovich Levitsky invented the Bellows camera. The correct option among all the options that are given in the question is the last option or option "D".
2. The substance with which the first photograph was made from, was Bitumen. The correct option among all the options given in the question is the first option or option "A".
3. Kodak DCS 100 was the first commercially available digital camera. The correct option among all the options that are given in the question is the first option or option "A".</span>