Some snakes have special sensory organs that detect the infrared region of the electromagnetic spectrum. Compared with human vision, these snakes can sense electromagnetic waves that have a lower frequency and a shorter wavelength.
a higher frequency and a longer wavelength.
a lower frequency and a longer wavelength.
a higher frequency and a shorter wavelength.

Based on the observation that only male crickets produce a song, you hypothesize that a male's song is a form of communication to potential mates. you set up a simple experiment to test this hypothesis. in the laboratory, you place a male snowy tree cricket in enclosure a, which is adjacent to enclosureb. in enclosure b, you place other insects, one at a time, and observe their responses to the male's song. the enclosures are designed so that the two insects being tested cannot see or smell each other, but sound is transmitted from enclosure a to enclosureb.