27. In a zoo, a big aquarium has a side wall with small glass windows, through which visitors can watch the fish. A circular glass window of radius 5 cm is located in that wall 3.5m below the water's surface. (a) What is the water pressure on that window? (b) What is the total force that the water exerts on that window? 28. A reservoir at the top of a high-rise building is directly connected to faucets in floors below. The water level in the reservoir is 95 m above street level. What would be the pressure at a closed faucet (a) 82 m above street level? (b) 6 m above street level? 29. What is the pressure in pascal of (a) 80 mm of mercury? (b) 760 mm of mercury? (c) of 10m of water? (d) 0.8m of water?