a) vì E,F là trung điểm của AB , CD nên : AF // FD và AE=FD , AF // ED và AF= ED,=> AEFD có EF // AD và EF =AD , trong hình bình hành AECF có : AF // EC , AF // EC

Hello every one , I feel happy that I’am living in a vilagge in trung thanh comune ò Thai Nguyen province . I like living in the countryside because of some reassong , environmenttally speaking . It is a peacatul place . the ải is fresh ,i’ts not noisy , very peaful . vutside i don’t like rural life because there are not many good school and means transport are very poor . we can enjoy healthy natural conditions with out worrying much about environ mental pollution . moteover , rural lite is also easier that in cities , to sum up , except in come matters , the country side is a better residence than citiers .