A student performs an experiment by ringing a bell in the air and in a pool and measuring the time it takes for a friend to hear the bell. In one or two sentences, make and justify a hypothesis on which medium the friend would hear the bell the fastest.

How does this excerpt develop the central idea that espionage during the civil war was often carried out by untrained citizens? it enhances the reader’s understanding by explaining why training was unnecessary. it changes the reader’s perception of what information a spy was able to obtain. it explains an ordinary person’s motivation for conducting espionage against the enemy. it adds moral complexity to espionage, due to the use of secret and dangerous methods.