Which statement about air masses and fronts is correct?
a)
only a front is the movement of a weather system.
b)
an air mass is a large body of air that takes on the characteristics of the area over which it forms, while a front is a narrow region separating two air masses of different densities.
c)
a front takes on the characteristics of the area over which it forms, while an air mass is a narrow region separating two different densities areas.

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.

2. cheryl hears a new song on the radio every day during the week on her commute to work. surprisingly, when the song comes on at a party on saturday night, she knows most of the words without trying. describe the three ways that we use cognition to learn without reinforcement. which type of cognitive learning without reinforcement best explains how cheryl knew the song lyrics? explain your answer.

What goes in and out of a cell respiration?