QUESTION: Fix punctuation: Prismatic cover for IP20 is optional and must be ordered separately
ANS: Prismatic cover for IP20 is optional and must be ordered separately.

QUESTION: Fix punctuation: His poetic work is marked by sadness anxiety depression and the search for the meaning of life
ANS: His poetic work is marked by sadness, anxiety, depression and the search for the meaning of life.

QUESTION: Fix punctuation: two stripping blades for cutting and stripping telephone ribbin cable 4P6P8P in a single operation
ANS: two stripping blades for cutting and stripping telephone ribbin cable (4P/6P/8P) in a single operation

QUESTION: Fix punctuation: Length 405 cm Width of 9 mm Thickness 21 mm
ANS:
Length 40.5 cm. Width of 9 mm. Thickness 2.1 mm.