<span>The type of map that shows the type and age of
rocks in an area is called a Geologic Map. A geologic map is a special-purpose
map that represents the distribution of diverse types of rocks, as well as
locations of different geologic structures such as faults and folds. This map
is the main source of information for various aspects of land-use planning,
especially in the placement of transportation systems and buildings. Although
they are typically depicted as two-dimensional, they can also be illustrated in
its third or fourth dimension depending on the type of information needed to be
taken. </span>
Answer:
Specific gravity is the density of asubstance divided by the density of water. Since (at standard temperature and pressure) water has a density of 1 gram/cm3, and since all of the units cancel, specific gravity is usually very close to the same value as density(but without any units).
