A mathematical means to present the curved surface of Earth on a flat surface perceptual region
functional region
map projection
spatial perspective
relief
planner projection
formal region
absolute location
relative location
great circle route

Answer primary waves;

It's either  a. chiang kai-shek and the nationalists turned against the communists and killed hundreds of them. orb. hundreds of peasants were killed in shanghai during the period of warlord rule.  if we take into account that there was warlord rule at the time, i think that it's b (not entirely sure though)just my best thoughts.