协同和耗散
参考答案:
协同和耗散是系统科学方法论另外两个基本概念:
协同就是子系统相互关联引起的某种同向协作运动
耗散,则是一种开放系统与外界交换物质和能量的运动。
化简:
(1)5a2+3ab﹣4﹣2ab﹣5a2
(2)﹣x+2(2x﹣2)﹣3(3x+5)
He came back late, _____ which time all the guesses had already left.
A.by
B.at
C.during
D.after