If velocity is positive, which would most likely yield a negative acceleration?

a final velocity that is faster than an initial velocity.
a time that is less than a half hour.
an initial velocity that is faster than a final velocity.
a time that is greater than a half hour.

By definition, we have to:

Where,

vf: final speed

vo: initial speed

a: acceleration

t: time

Clearing the acceleration we have:

Therefore, for the acceleration to be negative, we observe that the initial velocity must be greater than the final velocity.

An initial velocity that is faster than a final velocity.

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