在计算机场客货吞吐量时，（）不计算在内。 A.旅客 B.邮件 C.货物 D.手提行李

能同时被2、3、5整除的最大三位数是______．

设串s1="Data Structures、with Java"，s2="it"，则子串定位函数index(s1，s2)的值为 ( )

A．15

B．16

C．17

D．18

Bluetooth is a universal radio interface in the (1) frequency hand that enables portable electronic devices to connect and communicate wirelessly via short-range, ad hoc networks. Each unit can simultaneously communicate with up to (2) other units per piconet. Moreover, each unit can simultaneously (3) to several piconets. Eliminates the need for wires, cables and connectors for and between cordless or mobile phones, modems, headsets, PDAs, Computers, printers, projectors, local area networks, and so on, and paves the way for new and completely different devices and applications. Technology Characteristics (4) symbol rate exploits maximum available (5) bandwidth。

5（）

A．messages

B．certificates

C．applets

D．channel

为什么残单分析要保证进样量更准确？