①用二氧化锰和一定量的过氧化氢溶液制氧气时，所用二氧化锰的量偏多，所制得的氧气质量____．（填“偏多”、“偏少”或“不变”，下同）．

②量取水的体积时，仰视量筒读数为10mL，实际量取水的体积比10mL____．

    I'm Kate, and my sister____(be) Gina. I'm tidy, but Gina____(be not). In our room, my books and tapes____(be) in the bookcase. My ____(key) are in my schoolbag. I ____ (have) a clock. It's on the desk. ____(Gina) books are everywhere ----on____(she) bed, on the sofa and under the chair. The white model plane is____(she). It's under the desk. “Where are my keys? Where're my ____(ruler)? Where's my schoolbag?” Gina always ____(ask).

小明利用如图装置进行“探究光的反射规律”实验：