What investment decisions destabilized the economy during the 1920s?

People made investments based on the bull market instead of considering the value of the stock which led to destabilizing the economy.  

Speculation and buying on margin made people lose a lot of money. In consequence, the stock market and the economy became increasingly unstable. Loans couldn’t be paid back by speculators, and banks couldn’t cover depositors’ withdrawals because they had lost a lot of money in the stock market themselves.

This situation combined with some economic principles such as overproduction (when the good’s supply outpace their demand) made the stock market crash causing the Great Depression, the worst economic downturn in the history of the industrialized world. It lasted ten years, from 1929 to 1939.

overtime, the civil rights movement changed in a way that not only it benefited african-americans, but benefited other ethnicity's such as latinos, asians, or women too! that's why the results of the movement be called mixed.

the civil rights movement brought about tremendous changes. no longer were blacks denied the right to vote, to eat, shop, and swim where they , and more importantly, to attend integrated schools. despite its many accomplishments, however, the civil rights movement had its shortcomings. for example, many people, both young and old, lost their lives, homes, jobs, and families. still other individuals were so damaged by psychological trauma that they ceased being productive members of the community. the movement left intact the economic inequities that had contributed to the maintenance of segregation. and finally, racism remained alive and well long after the movement's end. like most movements of its kind, the civil rights movement left behind a mixed legacy of triumph and tragedy.

i'd assume india mainly because of how isolated japan was.   plus it is a whole china away.