Aflam,intai,aria,trapezului
A=(B+b)xH/2
H,se,afla,din,tr.dr.creat,de,coborarea,perpendicularei,din,A,pe,CD
H²=340²-160²
H²=(340-160)(340+160)
H²=180x500=>H=300
A=(500+180)x300/2=>A=680x150=>A=102000m²=10,2ha
Sporul,este,de,
360kg_______1ha
xkg_________10,2ha
x=360x10,2=>x=3672kg
3672kg_______η=100%
3213kg________y
y=3213x100/3672=>η=87,5%