Solution: Make the vertical line BC of DE in E and extend the intersection BC of AD in F. 。
∠ DCE = 30, then DE = CD/2 = 2;; CE=√(CD? De? )=2√3.
∫DE/EF = GH/HP ..
That is 2/EF= 1/2.
∴ ef = 4m。 Then BF=BC+CE+EF= 14+2√3.
AB/BF=GH/HP= 1/2, then AB=BF/2=(7+√3) meters.