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.

Two friends at different locations want to communicate with each other by sending low energy signals. which of the following methods can they use to communicate? a) produce x-rays using colliding electrons and send them to radios, which capture sound b) send messages using infrared radiation, which travel in the form of waves c) send radio waves through intervening media like radio and television d) produce sound waves using microwaves from heated objects

Which atom or ion is the largest? 0 a. 0 0 0 0 e. li

What are the three major branches of natural science? • earth and space science, life science, physical science •earth and space science, physical science, chemistry •physical science, life science, chemistry •life science, chemistry, physics