Which of the following statements is true? a. the nitrogen cycle is the most important cycle for life. b. the oxygen cycle is the least important cycle for life. c. life can be sustained without any of the cycles for life present. d. all cycles of matter are equally important for life to be sustained.

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.