题目

.（2010·福建省漳州市漳浦达志高三高考模拟试卷）    35. _____ the news, so far, has been good, there may be days ahead when it is bad.  A. While     B. When     C. As      D. Since 答案：A17．已知2a-7的平方根是±5，2a+b-1的算术平方根是4，求a+b的算术平方根．