Which of these statements best describes how an increase in atmospheric carbon dioxide contributes to global climate change? select one: a. water bodies dry up and cause less rainfall. b. forest fires become frequent which heats the earth. c. plant growth becomes rapid which increases rainfall worldwide. d. more sunlight is trapped by the atmosphere to cause global warming.

Two loudspeakers, 5.5 m apart and facing each other, play identical sounds of the same frequency. you stand halfway between them, where there is a maximum of sound intensity. moving from this point toward one of the speakers, you encounter a minimum of sound intensity when you have moved 0.33 m . assume the speed of sound is 340 m/s. part a) what is the frequency of the sound? part b) if the frequency is then increased while you remain 0.21 m from the center, what is the first frequency for which that location will be a maximum of sound intensity? express your answer to two significant figures and include the appropriate units.