how did we get 6000 as yhr answer ? please write down the formula and the steps to solving this ptoblem

On July 1, Madnd Corporation received $9,000 from New lberia Company for six months rent on a factory building and recorded it as a revenue. What adjusting entry wil Madrid make on August 31? O A. Rent Revenue B. Rent Revenue O C. Prepaid Rent 3,000 Unearned Rent Unearned Rent Rent Revenue Rent Revenue 3,000 6,000 6000 3,000 6,000 6,000 D. Unearned Rent 3.000