Step-by-step explanation:

Firstly we have to take variables to L.H.S and numbers to R.H.S

Hope it helps
There are 4 choices of meats from which you take 3, so there are
4! / (3! (4 - 3)!) = 4! / (3! 1!) = 4!/3! = 4
possible choices of 3-meat combos.
I think it’s GP! But honestly I have no clue! I’m sorry I hope someone can answer your questions! Sorry.