A box on a table is at rest and has a weight of 300 N. Two horizontal forces are being applied to the box. One force is 150 N to the right and the other one is 70 N to the left. What is the static friction between the box and the table?

Consider a u-tube whose arms are open to the atmosphere. now equal volumes of water and light oil (ρ = 49.3 lbm/ft3) are poured from different arms. a person blows from the oil side of the u-tube until the contact surface of the two fluids moves to the bottom of the u-tube, and therefore, the liquid levels in the two arms are the same. if the fluid height in each arm is 30 in, determine the gage pressure exerted by the person on the oil by blowing.