Vim/Unix Questions

Enter a Vim command to replace the string "dog" with the string "cat" everywhere in the file, including potentially multiple replacements on the same line:

Give the command to modify permissions on a file called "stuff.txt" to allow the group and others to read the file:

Enter a command to send the SIGKILL signal to a process with process ID 5645:

Enter a find command which searches starting in the current directory for all files ending in the ".java" extension and which were edited in the last half hour: