( (4)How many Pascal high vacuum is required for obtaining completely

1.	( (4)How many Pascal high vacuum is required for obtaining completely pure surfaceof metals ?(A) 10-8 to 10-9 (B) 10-8 to 10-10 (C) 10-6 to 10-9 (D) 10-8 to 10-7YY r
Answer» ANSWER: L didn't KNOW you are Soooooooofggg but I'm not SURE how to

( (4)How many Pascal high vacuum is required for obtaining completely pure surfaceof metals ?(A) 10-8 to 10-9 (B) 10-8 to 10-10 (C) 10-6 to 10-9 (D) 10-8 to 10-7YY r

Answer»

L didn't KNOW you are Soooooooofggg but I'm not SURE how to