$92,000 Net revenue - $52,000 Variable expenses = $40,000 Contribution margin. This ratio is only used from the perspective of deriving the lowest possible acceptable price for a unit. In reality, a variety of other pricing concepts can be used to establish higher price points for products.
Steam OS is possibly the best, most known and used cross platform Linux gaming distribution based on  Debian Linux, it is an assortment of numerous entertainment software, you can think of it as a complete gaming platform for Linux.
1 Microsoft Windows 7. Windows 7 is the best OS from Microsoft I have ever experienced... Easy to install... Crash free... Fabulous Graphics Support for HQ Games.. And more... Windows Vista is the worst OS from Microsoft... Very simple to install and better UI also best security.