What structures have been built in the Missouri River floodplain that could be destroyed or made unusable in a flood in which the river rose 20 feet

All of the following are reasons why people wanted the u.s. government to acquire hawaii except which one? a. it was an ideal location for a ship refueling station or permanent naval base. b. many americans knew it would be an ideal place to vacation. c. it was an ideal location for a lucrative sugar production industry. d. many missionaries hoped to convert the large native population to christianity.