"In 2019, Jamazon had operating income (EBIT) of $15 million, depreciation expense of $2.5 million, and interest expense of $1.5 million. Jamazon's tax rate is 50%. Jamazon's net operating working capital and fixed capital investments (i.e., the sum of change in net operating working capital and change in PPE) increased by $3 million, from 2018 to 2019. What is Jamazon's free cash flow? (in millions)"