饮酒后感到“烦闷解除”,逐渐形成了饮酒的嗜好,这属于()
A.惩罚
B.消退
C.负强化
D.正强化
E.以上都不对
参考答案:C
已知图示等直杆的轴力图(N图),则该杆相应的荷载图如下列何项所示(图中集中荷载单位均为kN,分布荷载单位均为kN/m。)
A.(A)图(a)
B.(B)图(b)
C.(C)图(c)
D.(D)图(d)
26. There was no doubt ____ it was in the supermarket _____ I lost my wallet yesterday.
A.whether, whether
B.that, that
C.that, whether
D.whether, that