Which voice part in this organum is singing the older gregorian chant (cantus firmus)?

The answer is Lower.

Explanation:

Gregorian song is the primary story of American melody or plainchant, a kind of monophonic, abandoned pure number of the Roman Catholic Church. The Gregorian hymn had as its goal the blessing and sermon of God. The clearness of the melodic wares promoted in the audience a unique center on priest, outdoors humanistic games.  Gregorian chant amplified principally in the Frankish states of westerly and fundamental Europe through the ninth and tenth times, with tracking enlarging and redaction. Although lay legend charges Pope Gregory  with lying Gregorian plainsong, learners suppose that it originated from a next Carolingian construction of Roman and Gallic-an chant.

≅200-130 milions years ago pangea splited in 2 continents

slitherio is the original. its the best friend of all middle schoolers. the man you can count any time you have some free time. slitherio is the guy you hang with while you're in the computer lab suppose to be doing "research or whatever". slitherio isn't just a game but a friend.

wormaxio is just a fake trying to squeeze its way into the friend group. trying to pretend its cool and your best pal but how long has it really been there for you, really. it only wants you as friend to boost its social status. wormaxio is just annoying fake pleb. no offense

you and have a wonderful day