The key to this problem is to regard sunlight as parallel light.

AB is a bamboo pole, AB= 1m, Bo =1.5m;

AB//CD//MN

CE=8, angle CED=30, CD⊥NO, so CD=4.

CD:AB=DO:BO，DO=4* 1.5/ 1=6

Ed. =EC？ -CD？ =64- 16=48

ED=4√3

NE= 19，

NO = NE+ED+DO = 19+4√3+6 = 25+4√3

MN:AB=NO:BO

MN = 1 *(25+4√3)/ 1.5 =(50+8√3)/3≈2 1.29(m)