A:t5•t5=2t5
B:t4+t2=t6
C:t3•t4=t12
D:t2•t3=t5
如图所示,倾斜的传动带以恒定的速度v2向上运动,一个小物块以初速度v1从底端冲上传动带,且v1大于v2,小物块从传动带底端到达顶端的过程中一直做减速运动,则( )
用所给词的适当形式填空
①I have two ____ (brother).
②There are two ____ (family) in the picture.
③ The old man has no ____ (son) or ____ (daughter).
④ My ____ (father) sister is my aunt.
⑤In the photo his mother's ____ (parent) are on the left.