某城市环保部门准备在临江的污水排水口处建立污水处理装置。采用该装置，现时点的投资为2000万元，此后每隔4年就需要500万元的维修清理费用。装置的寿命期可以认为是无限的。若资本的利率为12%，则整个运行期间的全部费用额的现值应为（）万元。已知：（A/F，12%，4）=0.20923。

A．2872

B．2642

C．3484

D．2986

Network managers have long (140) practical voice-over-IP (VOIP) solutions. VOIP (141) ease network management and decreases costs by converging a company’s telephony and data infrastructures into one network. And a VOIP solution implemented at a company’s head-quarters with far-reaching branch offices can (142) tremendous amounts of (143) in long distance phone bills, provided that solution delivers POTS-like voice (144) over the Internet.

A．get

B．put

C．save

D．waste