冰箱、家具和汽车属于（）。
A.耐用品
B.非耐用品
C.服务
D.便利品
参考答案：A
在国际单位制中，质量的主单位是______，弹力的主单位是______，功和能的主单位都是______；
9km/h=______m/s，3.2N/dm2=______Pa．
－Hi, Bruce. Here’s a letter for you.
－Thanks. I wonder_________.
A．who that letter was from
B．who was from that letter
C．who was that letter from
D．who from that letter was
