可出现于酸性、碱性或中性尿液中的是（）
A.尿酸
B.草酸钙
C.磷酸钙
D.尿酸钙
E.磷酸铵镁
参考答案：B
— I’ll be away on a business trip. Would you mind receiving my email for me?
— Not at all. _______.
A．I’ve no time
B．I’d rather not
C．I’d like it
D．I’d be glad to
图14-18桁架结构1杆轴力为（）。
A.0
B.
C.
D.
