Volatility: Empty memory associated with a particular process

I'm trying to understand how I can dump the memory associated with a process. Until now, I have been able to identify the PIDs of the processes that interest me (as well as their lag). However, I can not identify the exact plug-in / command of volatility that I should be running to actually extract the memory now.

The profile I am currently working on is LinuxUbuntu160403-040400-89×64.