Which element has 7 valence electrons

Select the correct answer. what is the wavelength of radio waves? a. between 1 x 10-3 and 1 x 10-1 meters b. less than 1 x 10-11 meters c. more than 1 x 10-1 meters d. between 1 x 10-8 - 4 x 10-7 meters e. between 4 x 10-7 - 7 x 10-7 meters