A. presence of ozone detected by odour
B. hissing sound
C. faint luminous glow of bluish colour
D. all of the above
Correct Answer: all of the above ✔
Last Updated: September 29, 2021
A. presence of ozone detected by odour
B. hissing sound
C. faint luminous glow of bluish colour
D. all of the above
Correct Answer: all of the above ✔
Last Updated: September 29, 2021