A. argon and krypton
B. krypton and xenon
C. helium and argon
D. argon and xenon
Correct Answer:
Option B – krypton and xenon
A. argon and krypton
B. krypton and xenon
C. helium and argon
D. argon and xenon
Correct Answer:
Option B – krypton and xenon
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