Answer:
A law can no longer be in effect if Congress passes the law saying it has no effect.
Several of these questions are opinion, so I can't really help with those, but I can answer the first one.
After World War I, the League of Nations was created to try to help keep the peace and solve problems between nations. The same went for the United Nations after World War II. There were also the treaties that ended the wars. (You'll have to decide whether or not these were actually successful.)
The ruler became corrupt and uses his powers to further his own interests instead of working for the common good.
There were several reasons why large numbers of Hindus and Muslims <span>migrated immediately after India gained its independence but the best option is "</span>(4) The subcontinent was divided into countries
based primarily on the location of religious
<span>majorities"</span>
