What are the mechanical properties of a geotextile that are of most importance when using it as a separator in an unpaved road situation with only stone base above it and relatively firm soil below it?

Hydraulic fluid with a sg. of 0.78 is flowing through a 1.5 in. i. d. pipe at 58 gal/min. the fluid has an absolute viscosity of 11.8 x 105 lbf-sec/ft2. is the flow laminar, turbulent or within the critical range? give both a numerical reynolds number and a term answer.

Modern high speed trains do not have perpendicular expansion gaps where rails are joined end-to-end any more they are mostly welded together but what might happen if there was a spell of particularly hot weather that causes inspection of the tracks?

What is the major difference between thermoplastics and thermosetting plastics from the polymerization structure point of view?