从某建筑物顶部自由下落的物体，在落地前的1秒内下落的高度为建筑物高的 $\frac{3}{4}$ ，则物体落到地面的瞬时速度为（g取10m/s²）（   ）

阅读短文，从A、B、C、D四个选项中，选出可以填入空白处的正确答案。
    Look at this picture. It is 1 nice classroom. In the picture, you can see a teacher's 2 on his desk. It's a Chinese book. Eight desks and eight chairs in the room. You can see a girl and 3 boys.
    The girl's 4 is Julia. She is eleven. The boy 5 a black hat is Tom. The other boy is Tony. They 6 the same coats and they are the same age. I 7 they are twins. Tom is a 8 boy. A book is in his hand. You 9 see the teacher . 10 is the teacher? He is taking the photo

下图为漫画《沉重的铁锤连续地打在蒋介石的脊骨上》，图中三个铁锤分别指刘邓、陈谢和陈粟，这幅漫画所反映的事件意义在于