Radio wave radiation has wavelengths from 10 to 1000 m, whereas the wavelength region for X-ray radiation is 1.0×10-11 to 1.0×10-8 m. We can say that: 1. The frequency of radio wave radiation is X-ray radiation.
2. The speed of radio wave radiation is X-ray radiation.

a electronegativity decreases beacuse the size of nucleus is bigger.

b. is the answer hoped i        

i think it's c. if you look search electronic symbol on google and then click on wiki it shows you a

it is stable as it is in group 0 which have full outer shells of electrons