A：史蒂芬孙
B：瓦特
C：哈格里夫斯
D：富尔顿
—_____________ has Hong Kong been back to our motherland?
—For 20 years. How time flies!
________ my father _______ my mother is able to drive a car. However, they are going to buy one.
填写单位：玉林同学身高170 ____，温水的温度为50 ____．液体体温计是利用液体 ____的性质制成的．
有若干标有“6V 0.5A”的小灯泡；此小灯泡正常发光时的电阻为 ____Ω，电功率为 ____W，若把两个这样的灯泡分别串联、并联后分别接在6V的电源上，则两种情况下电路的总功率之比为 ____
