老年人不宜练健美。（）
参考答案：错
I think Jack likes the pop music. _____ he doesn't. [ ]
A. In fact
B. As well as
C. In order to
D. A little bit
已知一个氘核和一个氚核聚变成氦原子核时放出17.6 MeV的能量,问4 g氘和6 g氚在聚变时总共可放出多少能量?
