脲酶抑制剂在农业生产的应用有哪些（） ["提高尿素的利用率","延长肥效期","提高氮肥的利用效果","防止果蔬制品褐变","可以抗病抗虫"]
IEEE的局域网模型包括三层次（含子网），分别是（）、（）、（）。
“长吉体”
锉刀的光边和凸凹工作面各有什么作用？
Your company has two domain controllers that are configured as internal DNS servers. All zones on The safer , easier way to help you pass any IT exams. 6 / 90 the DNS servers are Active Directory-integrated zones. The zones allow all dynamic updates. You discover that the contoso.com zone has multiple entries for the host names of computers that do not exist. You need to configure the contoso.com zone to automatically remove expired records. What should you do（） ["Enable only secure updates on the contoso.com zone.","Enable scavenging and configure the refresh interval on the contoso.com zone.","From the Start of Authority tab， decrease the default refresh interval on the contoso.com zone.","From the Start of Authority tab， increase the default expiration interval on the contoso.com zone."]
高处作业作业的级别分几级？依次为几米？
