Goodson Healthcare purchased a new sonogram imaging unit for $$300,000$ and a truck body and chassis for an additional $$100,000$ to make the unit mobile. The unit$-$truck system will be depreciated as one asset. The functional life is $8$ years, and the salvage is estimated to be $10\%$ of the purchase price of the imaging unit regardless of the number of years of service. Use classical straight line depreciation to determine the annual depreciation.