Why did Germany choose to launch unrestricted submarine warfare in 1917?

What happened as a result of the colonial victory at saratoga

What two things did former british prime minister winston churchill affirm in his iron curtain speech?

7. how did the early egyptians use the flooding of the nile river to their advantage? they diverted the water to flood their enemy's lands and destroy their crops. they created an easier way to travel to the mediterranean sea and the indian ocean. they established a new water-based athletic event for the ancient olympics in greece. they devised an innovative irrigation system, which created a surplus of food.