vivir in el/ella/usted form of the present tense and affimative tu command

Answer 1

In the present tense, the verb "vivir" (to live) in the "él/ella/usted" form is vive.

For the affirmative tú command, the correct form is vive as well.

So, both the él/ella/usted present tense and the affirmative tú command forms of "vivir" are vive.