Q: Can the MBP's RAM be expanded?

If you have a Retina model, RAM can not be added. Other models can have RAM added, but they will have only 2 slots, thus you would need to remove the existing RAM before adding higher capacity.

Yes it can (depending on model) either to 8GB or 16GB

You're welcome. You probably have the model below.

https://eshop.macsales.com/installvideos/macbookpro_13_unibody_mid12/

If you have a mid-2012 MBP 13-inch then you can use this Memory

16gb or Crucial ram for mac.

https://www.amazon.com/Crucial-PC3-12800-SODIMM-204-Pin-Memory/dp/B008LTBJFW/ref =sr_1_1?ie=UTF8&qid=1473289747&sr=8-1&keywords=16gb+ram+macbook+pro

Worked great in my MBP.

I recommend you do an SSD upgrade while you have the MBP open

This SSD worked great for me.

OCZ trion-150-series

https://www.amazon.com/Toshiba-OCZ-Trion-Internal-TRN150-25SAT3-240G/dp/B01B4NUK MY/ref=sr_1_1?ie=UTF8&qid=1473289844&sr=…

My MBP performs great now. Just like a NEW $2000 MBP.

You can do these upgrades for as little as $120