3. The surface tension of water is 72.8 and 58.0 mN m at 20 and 95C respectively. The density of water is 0.988 and 0.958 g cm at 20 and 95C respectively. Calculate the height of the water column at these two temperatures for tubes with internal radii of (a) 1.0 mm, (b) 0.025 mm. 4. Capillarity: (a) Calculate the height of a water column between two glass plates separated by 0.05mm at 20C. Assume the plates are 5 cm in width and the contact angle is 0. Start by deriving the capillary rise equation for this geometry neglecting end effects. (b) Estimate the amount of reversible work that would need to be done to pull these plates apart, assuming that the glass remains water wet after they are separated. Make sure to use a few simplifying assumptions in your calculation. 5. Calculate the height of a water column if the two glass plates in Q4 formed an angle of 10 at the water surface. Start by deriving the expression for the height, using the diagram. What height will the water rise too? Assume the contact angle is 0 and T= 20C.