Which digit is in the one's place what is its value

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

Runner ran 1 4/5 miles on monday and 6 3/10 on tuesday. how many times her monday’s distance was her tuesdays distance

When i'm with my factor 5, my prodect is 20 .when i'm with my addend 6' my sum is 10.what number am i