Challenger App
Home
Exams
Questions
Notes
Blog
Contact Us
e-Book
×
Home
Exams
▼
Questions
Notes
Blog
Contact Us
e-Book
Home
/
Questions
/
പരിസ്ഥിതി
/
പരിസ്ഥിതി പ്രശ്നങ്ങൾ
No.1 PSC Learning App
★
★
★
★
★
1M+ Downloads
Get App
Ozone layer was discovered in?
A
1920
B
1913
C
1912
D
1915
Answer:
B. 1913
Related Questions:
' Hiroshima in Chemical Industry ' എന്ന ഭോപ്പാൽ ദുരന്തത്തെ വിശേഷിപ്പിച്ച സംഘടന ഏതാണ് ?
Which of the following is a primary treatment for water pollution?
Salinization occurs when the irrigation water accumulated in the soil evaporates, leaving behind salts and minerals. What are the effects of salinization on the irrigated land? (UPSC Civil Services Preliminary Examination- 2011)
What does the fertilizers and farm animal waste cause?
What of the following was adopted as the substitute for open-burning dumping grounds?