According to ASME Y 145 2009 how should reference dimensions

According to ASME Y 14.5 2009, how should reference dimensions be indicated? Surrounded by a rectangular box Enclosed in parenthesis Underlined Marked with an asterisk

Solution

reference dimension is repeat of dimension and is derived from other values on the drawing

according to ASME Y 14.5 2009 the reference dimensions must be enclosed within parenthses

hence, option 2 would be correct