American cities increasingly abandoned wooden construction for brick and steel in their downtown districts after a the development of the electric elevator and the skyscraper. b brickmaking became cheaper and iron was superseded by more durable steel for construction purposes. c the cost of brick and steel dropped markedly in the 1870s. d wooden tenements collapsed in the New York inner city in the 1880s. e the great Chicago fire of 1871.

e. the great Chicago fire of 1871.

Explanation:

In 1871 Chicago faced a fire of exorbitant proportions known as The Great Fire of Chicago. At that time most of the houses and buildings in the region were made of wood, which stimulated the growth of fire that managed to spread very quickly through the city, being fed by wood from the buildings, houses and even the streets. The fire caused the death of about 300 people and left more than 5,000 homeless. This tragedy discouraged the use of wood as a building material, which was replaced by bricks and steel.

b. major john c. frémont led a rebellion called the bear flag revolt.

explanation:

during the bear flag revolt, from june to july 1846, a small group of american settlers in california rebelled against the mexican government and proclaimed california an independent republic. the republic was short-lived because soon after the bear flag was raised, the u.s. military began occupying california, which went on to join the union in 1850. the bear flag became the official state flag in 1911.

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