Hey Dr., good to see you again.
a) Two units used for area measurement are:
• Square meters (m2)
• Hectares (ha)
b) Two types of surface areas in the context of land surveying are:
• Horizontal surface area: This is the area projected onto a horizontal plane, which is typically what is calculated for land plots using coordinates.
• Sloping surface area: This is the actual physical surface area of the land, taking into account its undulations and slopes. It is always greater than or equal to the horizontal surface area.
c) Calculate the surface area of the land.
The coordinates are given as (East, North). We will use the shoelace formula for the area of a polygon.
Points:
A: (x1,y1)=(364.392,674.345)
B: (x2,y2)=(526.937,715.825)
C: (x3,y3)=(682.910,562.826)
D: (x4,y4)=(561.039,328.426)
E: (x5,y5)=(385.491,351.813)
Step 1: Calculate the sum of products xiyi+1 (with yn+1=y1).
S1=x1y2+x2y3+x3y4+x4y5+x5y1
S1=(364.392×715.825)+(526.937×562.826)+(682.910×328.426)+(561.039×351.813)+(385.491×674.345)
S1=260773.8064+296568.0496+224213.9166+197305.5785+259850.5960
S1=1238711.9471
Step 2: Calculate the sum of products yixi+1 (with xn+1=x1).
S2=y1x2+y2x3+y3x4+y4x5+y5x1
S2=(674.345×526.937)+(715.825×682.910)+(562.826×561.039)+(328.426×385.491)+(351.813×364.392)
S2=355397.0267+489006.1825+315790.6620+126622.7507+128290.4709
S2=1415107.0928
Step 3: Calculate the area using the shoelace formula.
Area=21∣S1−S2∣
Area=21∣1238711.9471−1415107.0928∣
Area=21∣−176395.1457∣
Area=21×176395.1457
Area=88197.57285
Step 4: Round the area to two decimal places.
The surface area of the land is 88197.57squareunits.
d) Calculate the perimeter of the portion.
Figure 2, which is referenced in this part of the question, is not provided in the image. Therefore, it is not possible to calculate the perimeter of the portion without the additional information from Figure 2.
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