硫化物的结晶表面常含有亚硫酸盐，为此，在配制硫化钠标准溶液时，应取用大颗粒结晶，并用水快速淋洗后，再称量。
参考答案：对
按照先进性的原则，协调和平衡工期、质量、安全、环保与成本之间的对立统一关系，反映了()造价管理的思想。
A、全寿命期
B、全要素
C、全过程
D、全方位
Multipurpose Internet Mail Extension (MIME) is a (76) document messaging standard in the Internet environment. With MIME, users can send (77) E-mail messages that include audio, video, graphices, and text to any other user of a TCP/IP network. Richtext information can also be (78) into messages. It defines the fonts, formats, and (79) features of a document so the document can be easily (80) on many different types of systems.
A．color
B．size
C．design
D．layout
