On September 1, Northhampton Industries signed a six-month lease for office space, which is effective September 1. Northhampton agreed to prepay the rent and mailed a check for $12,000 to the landlord on September 1. Assume that Northhapmton prepares adjustments only four times a year: on March 31, June 30, Spetember 30 and December 31. (1) Compute the rental cost for each full month. (2) Identify and analyze the effect of the transaction payment of rent on September 1. (3) Identify and analyze the effect of the adjustment on September 30.