Which are examples of an expository writing style? Check all that apply.

More than a hundred million e-mails are sent around the world each day, and they are all vulnerable to interception.
Other attacks include the use of viruses and Trojan horses.
But how can you bury a mountain of soil? Before long, the army engineers came up with a plan that would allow them to do just that.
Only a small fraction of the information flowing around the world is securely encrypted.
Hall well understood the gamble the Germans were taking.
When the war began, Elizabeth Van Lew was considered a southern "spinster."