What was the key factor in thomas edison success in designing the light bulb

The roosevelt corollary, issued in 1904, was a revision to what earlier statement of u.s. foreign policy?

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

By choosing to resupply fort sumter, abraham lincoln risked a. abandonment of the fort by union soldiers. b. abandonment of the fort by confederate soldiers. c. the appearance of giving in to confederate secession. d. armed conflict with southern soldiers.