What work should a man do to walk up a subway escalator moving down with speed `v` ? The height of the escalator is `h`, and the man walks up the escalator at a speed u.

Preeti reached the metro station and found that the escalator was not working. She walked up the stationary escalator in time t_1 . On other days, if the remains stationary on the moving escalator, then the escalator takes her up in time t_2 . The time taken by her to walk up on the moving escalator will be :

Preeti reached the metro station and found that the escalator was not working. She walked up the stationary escalator in time t_1 . On other days, if the remains stationary on the moving escalator, then the escalator takes her up in time t_2 . The time taken by her to walk up on the moving escalator will be :

Preeti reached the metro station and found that the escalator was not working. She walked up the stationary escalator in time t_1 . On other days, if the remains stationary on the moving escalator, then the escalator takes her up in time t_2 . The time taken by her to walk up on the moving escalator will be :