题干
It was not _____ she took off her dark glassed ___ I realized she was a wellknown actress.
A： what, that
B：until , that
C：until, whe
D：when , the
答案(点此获取答案解析）
B
+ 2x + log2x的值域是 {3, 
－1, 5 + 
, 20}，