How do you find the net force of 225 N

Adding more pulleys to a system of pulleys needed to lift an object. a. increases the force b. decreases the force c. increases the amount of work d. decreases the amount of work

If you place a magnet under a clear dish, and sprinkle iron fillings over it, above what part of the magnet will most of the fillings gather

The vapour pressure of benzene is 53.3 kpa at 60.6 °c, but it fell to 51.5 kpa when 19.0 g of a non-volatile organic compound was dissolved in 500 g of benzene. calculate the molar mass of the compound.