A science teacher ran a marathon. After the race she showed her students the silver blanket she was given to keep her warm. A group of students investigated how the colour of the blanket affected how much infrared radiation is absorbed

In summary the blanket that is metallic reflects electromagnetic waves

Explanation:

The teacher running the marathon generates a quantity of heat that the body must release to keep its temperature constant, one of the ways to release this energy in the form of electromagnetic radiation in the infrared range.

The matte with is silver should be metallic, so it reflects light at all wavelengths, so that the infrared light returns to the body and decreases the radiation radiation emitted, thus keeping it warmer.

In summary the blanket that is metallic reflects electromagnetic waves