I'm not ____(允许) to watch TV after lunch.
海蜇、海葵等腔肠动物,排出食物残渣的结构是( )
— Where is Mr. Green, do you know? I have something to tell him.
— He to Hong Kong for a meeting. He home three days ago.
若存在实数x∈1,2满足2x2﹣ax+2>0,则实数a的取值范围是____ .
图为某同学用目镜10×、物镜10×的显微镜所观察到的植物细胞有丝分裂装片的视野图象,当他换上40×物镜,直接调节细调节器观察,则( )