I need to calculate its depreciation at 2019/12/31 and use the mid-quarter convention. How to do it?

Peter made an investment in GPS equipment, which he will use in his consulting business. He placed this in service on October 1, 2019, and paid $122,000. The equipment has a 7-year class life. He does not want to expense any of the cost under Section 179 or take bonus depreciation on the machine but will use MACRS to calculate his depreciation deduction in 2019