How did the German Submarines Violate Neutral Rights

The neutral rights for US Merchant ships were legitimate targets during war but enemy ships was suppose to have a way to assist the crews of the merchant ships. The German submarines didn't have any way to assist the sunken crews. Explanation:

the french revolution was when many people were persecuted for disagreeing or making separate government

can someone me with this question:  

1) the end of the conflict between the north and the south didn’t just mark the end of a war; it marked the end of an entire way of life.” which statement best describes what this statement means?  

a) the southerners were no longer free and were controlled by the northern states.

b) the industrial economy in the north was not sustainable.

c) slavery became illegal, which changed completely the south’s labor force and the agricultural economy was destroyed.

d) the states decided to relinquish their independence and return to britain’s rule.