1. Sep1st, 2020 Business bought $1,500 merchandise inventory from EPC Inc., paid in cash
2. Sep2nd, 2020 Business sold $3,200 inventory to MKI Ltd on account, the cost is $800.
3. Sep4, 2020 Business bought $5,000 inventory from LPR Inc. , the money will be paid in the future
4. Sep18, 2020 Business received MKI Ltds money in full.
5. Sep21, 2020 Business purchased inventory $4,300 from UCY Enterprise, the money will be paid in the future.
6. Sep23, 2020 Business paid LPR Inc in full.
7. Sep28, 2020 Business found defective product, so returned $350 inventory to UCY enterprise.

Please write down the entries for the above transactions( please also show me the calculations according if the entry amount is not the same as the transactions)