Answer: 
GDP contribution is $6.
Explanation: GDP refers to the market value of final goods and services produced withing the national territory of a country.
Using the value added method, we can calculate GDP by summing up the value added at each level of production.


Or
Using the expenditure approach, GDP is the market value of the final good sold to the customer.
GDP = Cost of bread to the engineer = $6
Mass customization (build to order)
Answer:
The correct answer is A
Explanation:
Natural monopoly is the kind of monopoly which exists because of the high start up costs as well as the powerful economies of scale for conducting or performing a business in a particular industry.
And for this type of monopoly to exist , a firm or business need that the long run average cost curve will exhibit the economies of scale by the relevant range of the market demand.