The force of interest at time $t,$ where $t$ is measured in years, is given by:

$(t)=\{\begin{array}{cc}0\mathrm{.}002+0\mathrm{.}01t+0\mathrm{.}0004t^2,& 0t<mn\; id="EditorElement\_3490857">6</mn>\\ 0\mathrm{.}01+0\mathrm{.}003t,& 6t<mn\; id="EditorElement\_3490890">1</mn><mn\; id="EditorElement\_3490891">0</mn>\\ 0\mathrm{.}04,& t10\end{array}$

Calculate the present value at time $0$ of a continuous payment stream of RM$120$ per annum payable from time $10$ to time $15.$