My mother woke me up at six this morning. (—般疑问句)
____ your mother ____you up at six this morning?
能够自动发光的物体称为____。
鉴别两瓶失去标签的盐酸和硫酸溶液,可使用下列试剂中的( )
估算(用计算器验算)
30×98≈____
33×8≈____