What type of scientific tools would be needed for this investigation? Why?

Which region was almost every country colonized by an imperial power in the 19th century

Soon-yi's house has a hexagonal window made up of six identical equilateral triangles as pictured below.

The quote below is an excerpt from the charter of the united nations: "the purposes of the united nations are: to maintain international peace and security, and to that end: to take effective collective measures for the prevention and removal of threats to the peace, and for the suppression of acts of aggression or other breaches of the peace, and to bring about by peaceful means, and in conformity with the principles of justice and international law, adjustment or settlement of international disputes or situations which might lead to a breach of the peace . " source:this section implies that the united nations is prepared to do what to keep world peace?