Which development  most  contributed to the start of the second industrial revolution in the late 1800s?    a. the development of new agricultural tools    b. the invention of water-powered machines    c. the availability of inexpensive steel    d. the collapse of the railroad industry

c.

Explanation:

the avaliability of inexpensive steel,  the most prominent, thus with the first industrial Revolution, was in relation to inventions and discoveries, this time what boosted was undoubtedly the oil, the combustion engine, the use of steel and the use of water force in the generation of electricity , with the creation of hydroelectric plants.

here are some events that to cause increased conflict between the north and south

1) mexican cession- gaining modern day california, utah, arizona, and new mexico from mexico. caused southern and northern politicians to fight over whether or not there would be slavery in these newly acquired territories.

2) uncle tom's cabin- this famous book described the cruelty of slavery in the south during the antebellum period, causing more northerners to support abolition and southerners to resent the book as they felt it unfairly depicted southern society.

3) kansas- nebraska act- disagreements over whether or not kansas and nebraska would be free or slave states caused issues between northern and southern politicians in congress.

4) bleeding kansas- this fighting took place in kansas after congress allowed this territory to vote on whether or not they would have slavery. citizens were killed and buildings were destroyed during this fighting.

barack obama

44th president of the united states