Question 201883
Given {{{a= (t+4)^(-1)}}}
{{{v[0]=0}}}
{{{t=4}}}

Knowing that:
{{{v = at + v[0]}}}

So:
{{{v(t) = (t+4)^(-1)*(t) + 0}}}
When t = 4, we get
{{{v(4) = 8^(-1) * 4}}}
{{{v(4) = (1/8) * 4}}}
{{{v(4) = 1/2}}} m/s