Caused a statement where neither the Allied nor the central powers could advance there's a machine gun, tank, trench warfare, u-boat, battleship chemical weapon, gas mask airplane

i think the answer is b.

the causes of the dust bowls were severe droughts,   lands became dry and hard, temperature was higher than usual, hot and dry conditions killed crops, high winds. because of those factors, the winds kicked up dry soil and created clouds of dust.

every of the four river valley civilizations, religion played an enormous role in shaping and cultivating each civilization. this essay will briefly discuss how religion formed the river valley people’s government and view on geography. religion dictated how the peoples of the river valley civilizations managed government and geography.

            religious leaders played prominent roles in every river valley civilizations form of government. from ancient egypt and mesopotamia to china’s historic empire and the indus river valley, all the river valley civilizations had significant religious figures. in ancient egypt, the pharaoh was revered as a god and therefore was given his right as supreme governing authority in the eyes of the people. the elusive emperors of china gained there governing rights by a mandate of heaven creating long lines of dynasties until the common people of china felt the dynasty had lost the favor of the gods. chinese emperors were not only governing leaders but also the spiritual leaders of ancient china. mesopotamian and indus river valley priests were referred as has head officials who had vast amounts of authority in these two civilizations primitive forms of democracy. religion shaped the structure and social caste of the four river valley civilizations.

hope that