Write the chemical symbols for three different atomic cations with 20 protons

these would be positive ions (cations) which have lost their outer shell e-

to become like Ar

they are

K+

Ca++

Ga+++

Explanation: hope this helps

The 3 elements that has 3 electrons are:

Li, Be+ and B2+

Explanation:

Hoped that helped :)

h let me think

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

: )