An assembler uses seven key components in its final product. These components are purchased from different suppliers. Historical data shows that the reliabilities of the purchased components are as follows:ComponentReliability$10\mathrm{.}99020\mathrm{.}99030\mathrm{.}98040\mathrm{.}99550\mathrm{.}96560\mathrm{.}98570\mathrm{.}995$ The assembler purchases $2000$ units and inspects the products after production. The total direct cost of final products is $$500$ per unit. After inspection, $30\%$ of the defective items can be fixed and on average the rework cost is $$50$ per unit. Calculate the actual unit cost considering the reliability.