PLEASE I NEED HELP WHICH WOULD BE LESS DENSE AND EXPLAIN TOO :)

Need on both questionswill markbr />

Great amounts of electromagnetic energy from our sun and other bodies in space travel through space. which is a logical conclusion about these electromagnetic waves? their energy must be very their frequency must be very low these waves can travel without a medium they only travel through a vacuum of space

Adilute aqueous potassium nitrate solution is