It is a common trick to fill a straw with water, put your finger on the top of straw, and then watch as the water is suspended within the straw.
Assuming that water has a density of 1000 kg/m^3 and the atmospheric pressure is 101 kPa, then estimate the pressure (kPa) of the air inside of the straw at the top of water column. Neglect any surface tension effects.
