I really need this 2 ASAP , thank you for your help

3. A barber chair with a person in it weighs 2100 N. The output plunger of a hydraulic system begins to lift the chair when the barber's foot applies a force of 55 N to the input piston. Neglect any height difference between the plunger and the piston. What is the ratio of the radius of the plunger to the radius of the piston? 4. The density of ice is 917 kg/m3, and the density of seawater is 1025 kg/m3. A swimming polar bear climbs onto a piece of floating ice that has a volume of 5.2 ma. What is the weight of the heaviest bear that the ice can support without sinking completely beneath the water