Ohm. Because of that surface resistivity and the surface resistance are often mixed up. In order to differentiate between the two, surface resistiv-ity is often expressed also in Ohm/square (Î©/sq.) which is not a valid unit from the dimensional anal-ysis point of view. 2 Surface resistivity and surface resistance 2.1 Current density and surface cur-
The median age of the world's population was estimated to be 30.1 years in 2016, with the male median age estimated to be 29.4 years and female, 30.9 years.
1960 - 2015. 1  Population ages 0-14 (% of total) 2  Population ages 15-64 (% of total) 3  Population ages 65 and above (% of total)  Population growth (annual 1  %) Population, female (% of total)  Population, 1  total. Researchers in R&D (per million people)  Technicians in R&D (per million people)