Why aren't descriptive investigations repeatable?

Descriptive investigations are not repeatable because they are based only on observations made at a single point in time. The results may vary at a different time. In addition, descriptive investigations do not contain variables that may indicate cause-and-effect relationships.

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.