On basis of straight-line depreciation method,
Yearly depreciation expense = [Cost of investment - Salvage value] / life
In the current case, salvage vale is assumed to be $0 and the life is 7 years.
Total investment = $4 m + $ (15,000/1,000,000) m + $3 m = $7.015 m
Therefore,
Yearly depreciation expense = 7.015/7 ≈ $1.002 m