1. Horizontal planting: 40 ÷ 5+ 1 = 9 Vertical planting: 40 ÷ 4+1=1tree [the distance between two trees is 4m, and the sum of surrounding areas must be added after demolition].

2.3 m =300 cm

30+20=50 cm

300/50=6 models

You can cut it into six sections.