Siicon and selenium which is non metal

Question : Curie point is the temperature at which 

Option 1: Matter becomes radioactive

Option 2: A metal loses magnetic properties

Option 3: A metal loses conductivity

Option 4: Transmutation of metal coures

Question : Which s-block element is a silvery-white metal used in an alloy with copper or nickel to make gyroscopes, springs, electrical contacts, spot-welding electrodes and non-sparking equipment?

Option 1: Beryllium

Option 2: Rubidium

Option 3: Francium

Option 4: Caesium

Question : A metal ball and a rubber ball, both having the same mass, strike a wall normally with the same velocity. The rubber ball rebounds and the metal ball does not rebound. It can be concluded that:

Option 1: The rubber ball suffers a greater change in momentum

Option 2: The metal ball suffers a greater change in momentum

Option 3: Both suffer the same change in momentum

Option 4: The initial momentum of the rubber ball is greater than that of the metal ball

Question : Which theory discusses the relationship between ligand bonding and degradation of d orbitals in metal complexes and the geometry of metal complexes and the splitting of d orbitals?

Option 1: Crystal field theory (CFT)

Option 2: Ligand field theory (LFT)

Option 3: Valence bond theory (VBT)

Option 4: Molecular orbital theory (MOT)