If a line segment AB 200% what is the line segment of 100%

Which product is positive a is 2/5 -8/9 -1/3 -2/7 b is -2/5 8/9 -1/3 -2/7 c is 2/5 8/9 1/3 -2/7 d is -2/5 -8/9 1/3 2/7

Me! 50 points! why does when we come home, our door is unlocked and there is grease on the door knob, me solve this , and i don't know what category this goes under

Can someone me out here and the tell me the greatest common factor