The earth’s atmosphere is an envelope of gases present upto a height of about ______________ kms?

A. Idle running
B. Acceleration
C. Cruising
D. Deceleration

A. 1000 to 2000
B. 3000 to 6000
C. 6000 to 9000
D. 10000 to 100000

A. Mercury
B. Arsenic
C. Aluminium
D. Lead

A. Foaming from boilers
B. Its dissolved oxygen content
C. Its silica content
D. Caustic embrittlement

A. CO, SO2 & H2S
B. CO2, NO & SO3
C. CO2, H2S & NO2
D. SO3, NO2 & CO2

A. Hearing loss
B. Rupture of ear drum
C. Nervousness & fatigue
D. All A., B. & C.