The metal used for making radiation shield is

While passing through an applied magnetic field,which of the following undergoes the maximum deflection?

Which formula represents the rest mass of an electron?

Which of the following coloured light has the highest energy?

Which parameter is indicated by the number of waves passing through a given point in one second?

Identify the correct statements from the following:
$I$) Isotopes of an element show different chemical behaviour
$II$) Lyman series of lines of hydrogen spectrum appear in $UV$ region
$III$) The oscillating electric and magnetic field components of electromagnetic radiation are perpendicular to each other and both are perpendicular to the direction of propagation of radiation