An introduction or an explanation about what will follow

Who is the executive branch checking when the president calls a special session of congress

Which best describes the“brain trust” franklin roosevelt promised to make part of his administration? a group of america’s most successful businessmen, who would fix the economya group of hoover’s economic advisers, who would undo previous damage to the economya group of smart advisers, who would assist roosevelt in guiding the nation forwarda group of military veterans, who would assist roosevelt in putting americans back to work

The second westward surge reached the: mississippi river, appalachian mountains, oregon territory