若使用电解质粉代冰晶石进行装炉,电解质粉中氟化钙含量在()以上时,一般不考虑再使用氟化钙了。
参考答案:2%
堤防填筑作业面要求是( )
A.分层统一铺土、统一碾
B.分层分片铺土、统一碾压
C.分层统一铺土、分片碾压
D.以上选项都正确
E.上下层分段接缝错开
Pharming is a scamming practice in which malicious code is installed on a personal computer or server, misdirecting users to ______ Web sites without their knowledge or consent. Pharming has been called "phishing without a lure". In phishing, the perpetrator sends out legitimate-______ e-mails, appearing to come from some of the Web’s most popular sites, in an effort to obtain personal and financial information from individual recipients. But in pharming, larger numbers of computer users can be ______ because it is not necessary to target individuals one by one and no conscious action is required on the part of the victim.In one form of pharming attack, code sent in an e-mail modifies local host files on a personal computer. The host files convert URLs into the number strings that the computer uses to access Web sites. A computer with a compromised host file will go to the fake Web site even if a user types in the correct Internet address or clicks on an affected ______ entry. Some spyware removal programs can correct the corruption, but it frequently recurs unless the user changes browsing ______
A. habits signature B. manageability C. efficiencyD. address