Sorry if these have already been answered. I have had a look, but can't find them :
3a. One takes a backward view in it (10) - - - - O - P - - T
3d. Deseter had revolutionary square toothed bar (7) - - T - H - T
4d. Skin treatment centre (7) - - N - E - Y
Many thanks indeed in advance. I know I am going to kick myself.