Answer:
Magnesium and Bromine
Explanation:
I just took the test, and Magnesium has 7 electrons and Bromine has 2 valance electrons making the transfer a lot easier. In the first choice, Krypton already has 8 valance electrons therefore it cannot transfer or accept any more which rules it out as a possible answer. Calcium has 2 valance electrons and Potassium has 1 meaning it couldn't make a full shell of 8 and cannot make a ionic bond. Iodine has 7 electrons as well as Chlorine which wouldn't be the answer because it would have more than 8 valance electrons.
The rays of the electromagnetic spectrum from shortest to longest wavelength are: radio waves, microwaves, infrared rays, optical rays, ultraviolet rays, X-rays, and gamma-rays.
EDIT: He has these backwards, the shortest wavelength is created by Gamma-Rays and the longest is Radiowaves.
<span> Remember- high energy = short wavelength. </span>