The roots of polynomial $ p(t) $ are:
$$ \begin{aligned}t_1 &= -0.7047+1.372i\\[1 em]t_2 &= -0.7047-1.372i\\[1 em]t_3 &= 2.3047+4.2292i\\[1 em]t_4 &= 2.3047-4.2292i \end{aligned} $$Polynomial $ 100t^4-320t^3+1908t^2+2173t+5519 $ has no rational roots that can be found using Rational Root Test, so the roots were found using quartic formulas.