Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.

[Q]: in egyptain mythology sopdet was the goddess of the star sothis.
[A]: sopdet


[Q]: molar mass is the mass of a substance that has 6.022 × 10 atoms (avogadro's number).
[A]: molar mass


[Q]: the 1978–80 nordic football championship was the 12th nordic football championship.
[A]:
1978–80 nordic football championship