What geographic feature formed the boundary to the western part of the United States before the Louisiana Purchase?

Which roman emperor was responsible for a major shift in the dominate religious attitude of the roman empire?

Which of following most accurately describes china today?

Which answer best describes an advantage of shipping goods by canal? a) most towns would rather have canals then noisy railroads b) goods could travel very fast downstream in the canal system c) traveling by boat is a much more relaxing way to transport goods. d) heavy loads of goods could travel by boat more easily then if pulled by horses.