On 1 July 2021, Joe Surfer opened Hawaii Surfboards for operations. Joe, the owner contributed $30,000 of his personal funds to begin the business. The following transactions occurred during the month of July:

July 2: Paid the accountants fees of $2,000 to setup an accounting system for Hawaii Surfboards. July 4: Joe ordered brochures and surfing supplies on credit for $5,500. July 5: The business borrowed $45,000 over 5-years from the Bank of Hawaii to purchase office furniture and set up a business office at Waikiki Beach. July 14: A customer paid $600 in advance for surfing lessons to be performed in the second half of the month. July 17: The business paid for advertising on HawaiiOne radio of $10,000 for the full year. July 23: Paid for brochures and surfing supplies purchased on 4 July. July 28: After the first month of operations, Hawaii Surfboards earned 18,000 in revenue. Of this, 80% was collected in cash and 20% is due in 30-days.

Required:

a) Including the initial investment by the owner, prepare general journal entries for Hawaii Surfboards for the month of July.

b) Calculate the closing balance in Cash at Bank account at the end of the month.