# OS-9 Quiz: Linux Client Tools

Take this after studying `notes/OS-9-linux-client-tools.md`.

Reply with answers like:
`1B 2A 3D 4C 5B 6A 7D`

## Questions

1. Which Linux file lists local user accounts?

A. `/etc/resolv.conf`  
B. `/etc/fstab`  
C. `/etc/passwd`  
D. `/etc/hosts`  

2. Which Linux file stores password hashes and is normally protected?

A. `/etc/hosts`  
B. `/etc/shadow`  
C. `/etc/os-release`  
D. `/etc/fstab`  

3. Which command changes file permissions?

A. `grep`  
B. `df`  
C. `dig`  
D. `chmod`  

4. Which command shows live CPU, memory, and process activity?

A. `pwd`  
B. `cp`  
C. `top`  
D. `cat`  

5. Which command shows mounted file systems and free space in human-readable units?

A. `du -h`  
B. `df -h`  
C. `ls -l`  
D. `mv`  

6. Which package manager is common on Debian and Ubuntu-based Linux distributions?

A. `dnf`  
B. `regedit`  
C. `diskpart`  
D. `apt`  

7. Which command opens Linux manual/help pages?

A. `man`  
B. `mount`  
C. `sudo`  
D. `find`  

8. Which command shows the current working directory in Linux?

A. `ls`  
B. `cd`  
C. `pwd`  
D. `cat`  

9. Which command changes file ownership in Linux?

A. `chmod`  
B. `chown`  
C. `grep`  
D. `find`  

10. Which Linux command installs a package on Red Hat/CentOS-based systems?

A. `apt install`  
B. `brew install`  
C. `dnf install` or `yum install`  
D. `dpkg --install`  

11. Which command searches for text inside files in Linux?

A. `man`  
B. `df`  
C. `grep`  
D. `mount`  

12. Which file in Linux defines where file systems are mounted at boot?

A. `/etc/passwd`  
B. `/etc/shadow`  
C. `/etc/hosts`  
D. `/etc/fstab`  

13. Which Linux command shows disk usage for a specific directory?

A. `df -h`  
B. `du -sh /path`  
C. `top`  
D. `man`  

14. Which permission string means owner can read/write/execute, group can read/execute, others can read only?

A. `rwxrwxrwx`  
B. `rwxr-xr--`  
C. `rw-rw-rw-`  
D. `r--r--r--`  

15. Which command shows who is currently logged in to a Linux system?

A. `ps aux`  
B. `df`  
C. `w` or `who`  
D. `grep`  

## Answer Key For Instructor

1. C
2. B
3. D
4. C
5. B
6. D
7. A
8. C
9. B
10. C
11. C
12. D
13. B
14. B
15. C