Explanation: In order to begin an experiment, you must first define a problem or question that you will be answering. Then you must research the problem in order to form a hypothesis, or an educated guess. Then you should devise and execute an experiment to answer your question. The conclusions that you draw will either prove or disprove your hypothesis. Hope this helps!
The porpoise would hear its echo first because sound travels faster in water than in air. The bat would hear its echo first because the amplitude of sound waves ...