11. which of the following commands can be used to extract a tar file?
a. tar -vf
b. tar -xvf
c. tar -e
d. tar -v
12. which of the following commands can be used to create a tar archive file in verbose mode?
a. tar -v
b. tar -cvf
c. tar -c
d. tar -vf
13. in what file do you change default shell variables for all users?
a. /etc/bashrc
b. /etc/profile
c. ~/.bash_profile
d. /etc/skel/.bashrc
e. /etc/skel/.bash_profile
14. which two files in a user's home directory are used to customize the bash environment?
a. bash and .bashrc
b. bashrc and-bash_conf
c. bashrc and bashprofile
d. .bashrc and .bash_profile
e. bash.conf and .bash_profile
15. where are the default settings for the useradd command kept?
a. /etc/default/useradd
b. /etc/sysconfig/useradd.cfg
c. /etc/.useradd
d. /etc/defaults/useradd
e. /etc/login.defs
16. which protocol is used by ping?
a. tcp
b. udp
c. smb
d. icmp
e. ospf
17. if you suspect that a gateway machine on your network has failed but you are unsure which machine, which command will help locate the problem?
a. ps
b. netstat
c. nsloopup
d. ifconfig
e. traceroute
18. what is the binary conversion of the ip address 192.168.1.10?
a. 11000000.10101000.00000001.00001010
b. 01101010.11000100.10101000.00000001
c. 00000001.00001010.11000000.10101000
d. 10101000.00000001.00001010.11000000
e. none of the choices
19. your server logfile shows repeated connections to tcp port 143, what service is being accessed?
a. smtp
b. imap
c. pop3
d. pop2
20. the _____ is used by the local host to determine which hosts are on the local subnet, and which hosts are on remote networks.
a. dns
b. arp
c. gateway
d. netmask
e. routing protocol
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