What is the primary use of a remote access VPN?（）
A. to secure communication between two remote PCs
B. to secure communication between two remote offices
C. to secure communication betweenan remote PC and the corporate intranet
D. to secure communication between a corporate intranet and the public internet
【剪切】菜单命令的快捷键是（）。
A. Ctrl＋C
B. Ctrl＋X
Ctrl＋V
D. Ctrl＋Z
（）是指随机抽样调查中样本指标与总体指标之间的差异。
A. 抽样错误
B. 类型差异
C. 抽样误差
D. 抽样估计
企业用现金购买将于3个月内到期的国库券，是现金流出，构成现金流量。
A. 正确
B. 错误
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