Match List-I with List-II and select the correct answer using the code given below the Lists: 

List-I (Hypothesis/Theory)                                       List -II (Propounder)

A. Planetesimal Hypothesis                                  1. Kober

B. Thermal contraction theory                             2. Chamberlin

C. Geosynclinals Orogen theory                          3. Daly

D. Hypothesis of sliding continent                      4. Jefferys

Bright light is found to emit from photographer's flashgun. This brightness is due to the presence of which one of the following noble gases?

Which one of the following is not a characteristic of a compound?

Which of the following substances cause temporary hardness in water?

1) Mg(HCO₃)₂
2) Ca(HCO₃)₂
3) CaCl₂
4) MgSO₄
Select the correct answer using the code given below.

Which one of the following elements will be an isobar of calcium if the atomic number of calcium is 20 and its mass number is 40?