My Macbook Pro keyboard has 4 keys that stopped working

4, r, f, v stopped working two days ago in the middle of my class - i'm now using the keyboard viewer in order to type

If I click on these buttons when the keyboard viewer is open, it has no response - the other keys that are pressed light up on the viewer

I have an apple appointment tomorrow but I have class all day and was wondering if there was a way to fix it before then

I can't reset my PRAM because of the r key and have tried changing my input sources in system preferences

it's a macbook pro retina that I got for christmas