When does the cost of inventory become an expense?

Consider an economy where government expenditures are 10 and total tax revenues are 10. the supply of labor is fixed at 125 and the supply of capital is fixed at 8. the economy is described by the following equations. y k to the power of 1 divided by 3 end exponent l to the power of 2 divided by 3 end exponent c 2.5 + 0.75 ( y - t ) i 10 - 0.5 r the level of private savings is