Faculty of Science and Mathematics plans to build a water tank at the FSM pineapples farm to store water for the purpose of the farm. The water tank will be built in the form of a regular hexagonal prism. Suppose that each base edge measures 1.3 m and the apothem of the base measures 1.1 m with the altitude of 2.25 m. a. Prove formally that the total area of the water tank that needs to be painted is 21.84 m (assuming that the lower base needs not to be painted). [16 marks] b. Suppose that volume of 1 m can be filled with 1,000L of water. How much water can fill the water tank in (a)? (Justify for all the works)