The correct option is B 60m
Given−ABEisarighttrianglewithABashypotenuseand∠ABE=45o,BE=50m.BCDEisarectangle.Tofindout−AD=?Solution−ABEisarighttrianglewithABashypotenuse.∴∠AEB=90o.AgainBCDEisarectangle.∴∠DEB=90o.So∠AEB+∠DEB=90o+90o=180o.∴∠AEB&∠DEBarelinearpair.i.eAEDisastraightline.NowAEBE=tan45o=1.∴AE=BE=50m.AlsoDE=BC=10m.∴AD=AE+DE=50m+10m=60m.Ans−OptionB.