How is a niche like a person's job

Ineed to find the answer of this question because i dont understand it

Based on its chemical properties, identify the position of each chemical family on the periodic table.

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