A:物体的加速度越来越大
B:物体做匀减速运动
C:物体的速度越来越小
D:物体做变减速运动
(Ⅰ)证明:CD⊥AG;
(Ⅱ)若三棱锥E﹣BCF的体积为 16 ,求 FDPD 的值.
宏观上看,水是由____ 和____ 两种元素组成的;从微观上看,水是由____ 构成的,水分子中氢原子和氧原子的个数比是____ .
亲代的遗传物质传给子代是通过( )
①—Who is he?
—He's my father.
②— Who is she?
— She is my grandmother.
③—Who is she?
—She's my mother.
④—Who is he?
—He's my grandfather.
____