A 5kg object is acted on by a horizontal force, find the velocity when t = 5 seconds

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A 5kg object is acted upon by a horizontal force with a magnitude given by $F=3t^{-t}+t $. If the object has an initial velocity of 5 m/s find the velocity when $t=5$ seconds.

This question was on a revision sheet given to me, I believe it revolves around Newtons second law using the formula $R=ma$. Because the object is 5 kg ,this must be the value for $m$, with 5 being the given velocity, it could possibly be derived to become acceleration, meaning it would become zero. So I think I've misinterpreted the question and I also am not sure how to approach solving velocity.

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You can use Newton's second law to find the acceleration with respect to time since:

$$ F(t) = ma(t) $$

You have an expression for $F(t)$ and you also are given the mass. Once you have an expression for $a(t)$ notice that:

$$ a(t) = \frac{d}{dt}v(t) $$

where $v(t)$ is the velocity. Thus, we have that

$$ v(t) = \int a(t) dt $$

This will produce the velocity up to a constant of integration. You may use the initial velocity given to eliminate this.