题干
---William has asked me for a loan of 50 dollars. Should I lend it to him?
---Certainly. Because ______ he would try to borrow it from me.
A：otherwise
B：therefore
C：beside
D：however
答案(点此获取答案解析）
A
，且四面体的四个顶点在同一个球面上．则这个球的表面积为（ ）
