Convert from block [South, West U.S.] to femtometer

Unit Definition (block [South, West U.S.])
The Block is an informal unit of distance popular in the U.S. A block is the average distance between street intersections in the rectangular street grids common in most American cities. The length of a block is about 1/10 mile (160 meters) in USA cities in the South and West.

Unit Definition (femtometer)
a metric unit of length equal to one quadrillionth of a meter.