Who says dogs don't need to wear beautiful clothes? My dog Michael has many different kinds of1, and he likes them a lot. Look at him in the picture! He is2 a grey hat, a yellow shirt and red shoes today. And he also wears a3 of sunglasses. You look so4, Michael! I design clothes for Michael.It takes me a lot of free time, 5 I enjoy it. All of Michael's clothes are made 6good cotton. And they 7 him very well. Every time I take Michael out for a 8 in the park, I can hear people saying, “Oh, look at that dog. How fashionable he looks!” I'm very happy about it. It 9 that Michael is already a star. Walk for today, Michael. What? You want to play with the ball? All right, let's go! Oh, 10me! I'm putting on my sneakers.

某实验小组应用如图甲所示装置“探究加速度与物体受力的关系”，已知小车的质量为M，砝码和砝码盘的总质量为m，所使用的打点计时器所接的交流电的频率为50Hz，实验步骤如下：

A．按图甲所示，安装好实验装置，其中与定滑轮及弹簧测力计相连的细线竖直；

B．先不挂砝码盘，调节长木板的倾角，轻推小车后，使小车能沿长木板向下匀速运动；

C．挂上砝码盘，接通电源后，再放开小车，打出一条纸带，由纸带求出小车的加速度；

D．改变砝码盘中砝码的质量，重复步骤C，求得小车在不同合力作用下的加速度．

根据以上实验过程，回答以下问题：