1) one of the most formidable enemies of the tarantula (happen/happens) to be the scorpion. 2)the venom from tarantulas (is/are) as potent as a bee sting.

1) One of the most formidable enemies of the tarantula (happens) to be the scorpion.

(happens-singular , describing the word 'One' )

2)The venom from tarantulas (is) as potent as a bee sting.

(is- singular, describing the word 'venom')

Persona, Boy With Luv, Moon, & Inner Child, lol I couldn't pick one

Explanation: