Please help me out Describe how the Doppler effect explains why an approaching fire engine's siren has a high pitch.

Describe what happens to the energy of a wave if the frequency decreases.

Dry ice is solid carbon dioxide that is used in the transport of food and medicine. dry ice becomes a gas at –78.5°c without becoming a liquid first.

Although longitudinal waves can travel through all media types what is the disadvantage of this type of wave transmission? a) he efficiency of he wave transmission is greatly diminished as the media becomes less dense b) the oscillation of one set of particles has a huge impact on neighboring particles c) particles become too close together as they bump into each other making it more likely to hit other particles down the line

Which of the following are used in an electrochemical cell? a. electrodes b. electrolyte c. terminals d. all of the above