Need help problem 7 nd problem 8..

Problem 7 O Looking at the diagram, what is the conductor size of the feeder supporting the dry-type transformer? -225A 3*4/0, 1*4, 3'C Problem 8 Select a service transformer size for Administration facility with a total gross size of 60,000 square feet. The total connected load is 520 A at 480/277 V. Consider available transformer sizes and any additional UFC requirements. Problem 9 Which sheet is generally the best choice for indicating service conductor size