Solution: Articles of Incorporation
Answer: HYPOTHESIS, RAM

Written by Philip Z Loh

The puzzle presents a list of nonsensical questions each containing the word "which". Using "which" as a separator, we create a left half and right half, along with the given letter banks:

Left half Middle Right half
1. foggy phenomenon which Epic headquarters today? (7)
analog TV color system which commercial? (3)
belt which Super Bowl ambition? (2)
Catholic ceremony which Hadoken-using game character? (3)
father which skin opening? (4)
female emperor of China which FR regional rail system? (7)
Hamilton's number which what's after Turing as seen from One Esterra? (1)
lipstick brand started by two Franks which PK-using game character? (5)
NMSU telescope home which early 1900s chanson réaliste performer? (8)
pelt which necessity when at SEA?? (6)
religious ceremony which spasm? (8)
Saigon's new namesake which Seattle or Bellevue, e.g.? (6)
stake which PR time zone? (8)
traditional unit of distance which unpleasant noise? (7)
universal logic gate which Twilight Zone cookbook ingredient? (4)
AAAAAACEEEFGHIIIILLMMMNNNNOOOPPPRRRRSSSSTTTTUUW AAAAAACCCDDDDEEEEGIIIIIIKMMMNNNNNOPRRRRSSSSTTTTTYY

Each half is solvable to a short word or initialism. "Articles" from the title of the puzzle suggests that in lieu of "which", we should use either a definite or an indefinite article. Besides the first question, everything else is sorted alphabetically by the left half. This suggests that a reordering step is required.

We find that the right half of each question actually belongs to the "next" row, and make this chain of words that incorporate articles, alternating between "a" and "the", starting from the 1., along with the remaining letters from the letter banks:

Left half Left Middle Right Right half Index Extract
foggy phenomenon mist a ken Hadoken-using game character 3 S
NMSU telescope home apo the cary Epic headquarters today 7 C
lipstick brand started by two Franks mac a damia early 1900s chanson réaliste performer 8 I
traditional unit of distance li the ness PK-using game character 5 E
analog TV color system pal a din unpleasant noise 7 N
Saigon's new namesake ho the ad commercial 3 T
Hamilton's number ten a city Seattle or Bellevue, e.g. 6 I
pelt fur the st what's after Turing as seen from One Esterra 1 F
religious ceremony rite a id necessity when at SEA? 6 I
father pa the tic spasm 8 C
belt sing a pore skin opening 4 G
female emperor of China wu the ring Super Bowl ambition 2 U
stake ante a ter FR regional rail system 7 E
universal logic gate nor the ast PR time zone 8 S
Catholic ceremony mass a man Twilight Zone cookbook ingredient 4 S
R M

Indexing with the given numbers into the words we find the phrase: SCIENTIFIC GUESS. Following the spirit of incorporating articles, in this case "the", the first answer is therefore HYPOTHESIS. Using the leftover letters and "a", we find the second answer, RAM.

Author’s Notes

Part of the original plan for this puzzle was to get to HYPO THE SIS as separate chunks, but unfortunately that plan went under, or as they say in Greek, hypo. A previous draft did not present the first clue separately and required solvers to form a loop instead, but almost every single tester submitted SCIENTIFIC as they had interpreted the phrase GUESS SCIENTIFIC as an instruction.