1) First train leaves the Audley at $$9.00$$
2) The second train will leave Audley after $$100\quad minutes$$
$$=60+40\quad minutes$$
$$=1 \quad hour+40\quad minutes$$
Thus, second train will leave Audley at $$9.00+1:40$$
$$10:40$$
3) Third train will leave Audley at $$10:40+1:40$$
$$=12:20$$
4) Fourth train will leave Audley at $$12:20+1:40$$
$$=14:00$$ ($$2:00$$ at noon)