Who was president barack obama's first chief of staff, from 2009 to 2010?

Once the plague became airborne, how could it then be spread?

Plz which of the following provisions of the compromise of 1850 was designed to appeal to slave states? a. congress passed a strict fugitive slave law. b. the slave trade was banned in washington dc. c. texas agreed to give away some of its land so that the territory would be available for future states. d. california was admitted to the union as a free state.

List two reason that james k.polk gives for supporting the annexation of texas