Which of the following identifier names are invalid and why?

Ans:

a)Serial_no.InvalidWe cannot use any punctuation mark in identifier name
b)1st_RoomInvalidVariable name cannot begin with number
c)Hundred$ValidWe can use ‘$‘anywhere in variable name except at the beginning.
d)Total MarksInvalidWe cannot provide space between the names of variable.
e)Total_MarksValidWe can use ‘_’ anywhere in variable name.
f)total-MarkInvalidWe cannot use ‘-‘ in variable name as it is treated as system defined identifier.
g)_PercentageValidA variable name can begin with ‘_’.
h)TrueInvalidSystem defined identifier