Answer:
1 month
Step-by-step explanation:
The last coupon paid by this bond was made on August 1, 2018, and the transaction is made on September 1, 2018, therefore, only 1 month has passed since the last coupon was paid. Therefore, accrued interests will be charged for only 1 month.
When bonds are sold including accrued interests, they are said to be sold at their dirty price.