Answer
See below
Work Step by Step
We are given that $f(t)= (t -1)^2u_{2} (t)\\=(t-2+1)^2 u_2(t)\\
= (t-2)^2u_2(t)+2(t-2)u_2(t)+u_2 (t) $
Now,$F(s)= L[(t-2)^2u_2(t)+2(t-2)u_2(t)+u_2 (t) ]\\= \dfrac{2e^{-2s}}{s^3}+ \dfrac{2 e^{-2 s}}{s^2}+\frac{e^{-2s}}{s}$