Okay, let's solve this step-by-step:
1) Given: Actual area of plot = 1.28 hectares = 12800 sqm
Map area = 8 sqcm
2) To calculate RF:
RF = Map Area / Actual Area
= 8 sqcm / 12800 sqm
= 8 / 12800
= 1/1600
3) Length of scale = RF x Maximum length
= 1/1600 x 100m (let's take max length as 100m)
= 100/1600 cm = 6.25 cm
4) Draw a line 6.25 cm long and divide it into 10 equal parts to read up to 1 decimal place.
5) Draw a perpendicular line