肥皂溶于热的蒸馏水中,冷却后加盐酸中和,最后得到的沉淀是( )
A:氯化钠
B:高级脂肪酸钠
C:高级脂肪酸
D:甘油
如图是草原生态示意图,请回答:
We don't have enough nurses to look after the patients. At least _____ are needed.