Why did the Sumerians invent sailboats?

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

Humans during the paleolithic era used fire for each of the following purposes except a. for cooking meat b. for use as a weapon c. for heat and warmth d. for treating animal hides select the best answer from the choices provided

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.