Can anyone please help me?

1'109E Consider a U-tube whose arms are open to the atmosphere. Now equal volumes of water and light oil (,0 = 49.3 lbmfft3) are poured from different arms. A person blows from the oil side of the U-tube until the contact surface of the two uids moves to the bottom of the U-tube, and thus the liquid levels in the two arms are the same. If the uid height in each arm is 30 in, determine the gage pressure the person exerts on the oil by blowing. Air Oil Water 30 in 4 FIGURE P1109E