```---------- ---------- ---------- ---------- ---------- ---------- ---------- ----------
# The area of the Italian peninsula
X = T\$V1; Y = T\$V2
HF=4; BF=4
Plane(min(X),max(X), min(Y),max(Y)); polyC(X,Y, "cyan")

# The area using as a unit of measure the "squares" delimited by longitudes and
# latitudes
area = areaPol(X,Y); area
#  28.59358
# Its transformation into km^2 taking into account that 1 degree of latitude is 111 km
# (rounded value) and 1 degree of longitude in Italy is approximately 79 km (it is 82
# km at Napoli):
Area = area*111*79; round(Area,-3)
#  250737.1    251000
# Or:
signif(Area, 3)
#  251000
# The area of the Italian peninsula is actually 252000 km^2
#
# The Italian peninsula with a scale showing (approximately) the kilometers (and the
# distances from the centroid):

X1=X*79; Y1=Y*111
BF <- 4; HF <- 4; PLANE(min(X1),max(X1), min(Y1),max(Y1)); polyline(X1,Y1, "blue")
C <- centerPol(X1,Y1); C; POINT(C[1],C[2],"red")
#  963.0065 4827.3143
circl(C[1],C[2],200,"brown")
circl(C[1],C[2],400,"brown")
circl(C[1],C[2],600,"brown")
segm(1200,4800,1300,4800,"brown")
POINT(1200,4800,"brown"); POINT(1300,4800,"brown")
text(1250,4850,"100 km")

Other examples of use

```