恒星的光谱分类中，从O型到M型，恒星的温度由高到低。
参考答案：对
齐桓公任用_____改革内政。 [ ]
A．伊尹
B．管仲
C．楚庄王
D．秦孝公
Living in the central Australian desert has its problems, _____getting water is not the least.
A．as
B．of which
C．whose
D．for what
