A sample of hydrogen gas is mixed with water vapor. The mixture has a total pressure of 759 torr , and the water vapor has a partial pressure of 28 torr . What amount (in moles) of hydrogen gas is contained in 1.57 L of this mixture at 298 K

Using a wheel and axle, a farmer is trying to lift a bucket of water from the bottom of a well. the larger wheel has a radius of 40 cm compared to the axle that has a radius of 10 cm. if a bucket of water is 50 n, then how much effort is required to raise it? 12.5 n 200 n 2 n 500 n