A window washer pulls herself upward using the bucket-pulley apparatus shown in Fig. 4-48.(heres the pic. http://img126.imageshack.us/i/physcis.jpg/) The mass of the person plus the bucket is 70 kg. (a) How hard must she pull downward to raise herself slowly at constant speed? (b) If she increases this force by 8%, what will her acceleration be? For some reason i got wrong answers 686.7 N and 10.59 m/s^2, Why?