Only 2 or more 180 degree angles can be considered parallel.
I might be wrong but it should be 1
If y+6=15, then y=9. (9+6)divided by 3 would be 5, not 15.
F = 2.5p, where p is 1 large pizza
The first option
If these are all the side lengths then just multiply all of them together
Answer) 326,400cm^5