Balance-torque problem 2?

Another for review. How did you do it? A meter stick is supported by a knife edge at the 50 cm mark and has masses of .4 kg and .6 kg hanging from the 20 cm and 80 cm marks, respectively. Where should a third mass of .3 kg be hung to keep the stick balanced. a. 20 cm b. 70 cm c. 30 cm d. 25 cm also, An... show more Another for review. How did you do it?
A meter stick is supported by a knife edge at the 50 cm mark and has masses of .4 kg and .6 kg hanging from the 20 cm and 80 cm marks, respectively. Where should a third mass of .3 kg be hung to keep the stick balanced.
a. 20 cm
b. 70 cm
c. 30 cm
d. 25 cm

also,
An 800 N billboard worker stands on a 4m scaffold supported by vertical ropes at each end. If the scaffold weighs 500N and the worker stands 1m from one end, what is the tension in the reop nearest the worker?
a. 450 N
b. 500N
c. 800N
d. 850 N
1 answer 1