A:
B:
C:重合
D:不确定
As students, you must listen to the teacher attentively and keep a record ______ what the teacher says in class.
冰的密度是0.9×103kg/m3,有一块冰,它的质量是900g,它的体积是____m3;如果冰要全部融化成水,则水的质量是____kg,水的体积是____ m3。
45-5=40中,被减数是(45),减数是(5),差是(40)。