Please answer me ASAP A technique that uses a porous barrier (separation with pores) to separate heterogeneous mixtures is .

a. distillation

b. chromatography

c. filtration

d. crystallization

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