35. The work function of
Caesium is 2.14 e V. The
threshold frequency for
Caesium is
*

Explanation:

1 eV = 1.6 * 10⁻¹⁹ J

The work function is the minimum energy required to cause the photo-emission of electrons. The work function is dependent on the type of metal.  

Whereas the threshold frequency is the minimum frequency of light required to produce the work function energy. The work function is given by:

the answer would be   dignified - apex

so easy. just google the electromagnetic waves and it’ll pop up.