血缘家族
协方差绝对值越大，表示这两种资产报酬率的关系越疏远。（）
Which statements are true concerning NAT？ （） [" NAT provides 1 to manyaddress mapping."," NAT provides 1 to 1 address mapping."," NAT is only useful forTCP\/UDP and ICMP traffic."," NAT can be used for all IP traffic."]
协方差的绝对值越小，则这两种资产报酬率的关系越密切。（）
猪肉的结冰温度为（）。 ["0℃","-0.5℃","-1.0℃","-1.5～-2℃"]
教育公共关系特征和实质是什么？
