please no 1 aja tolong dijawab yaa...

skala = 1 : 20m = 1 : 2000

lebar gmbr = 4,25cm
panjang gmbr = 6cm

lebar asli = 4,25 x 2000 = 8500cm
panjang asli = 6 x 2000 = 12000cm

8500cm = 85m
12000cm = 120m

semoga membantu! :)