4245. Black cotton soil is not suitable for foundation because its-
permeabitily is uncertain
property undergo to volumetric change due to variation of moisture content
ব্যাখ্যা: ব্যাখ্যা: Black cotton soil is not suitable for foundation because it swells excessively when wet and it shrinks excessively when dry. So it is not suitable because of its property to undergo a volemetric change due to variation of moisture content