The following data relate to a closed economy of a country where all production takes place in two firms. Use the information in the table to answer the questions that follow:

Items	Firm A (in 000 Dollars)	Firm B (in 000 Dollars)
Sales	200	400
Raw material	100	60
Labour costs	80	160
Depression	16	40
Profits	4	140

(a)(i) Which of the items listed above is an intermediate input?
(ii) What happens to intermediate inputs in the calculation of the national income?
(iii) Calculate the Gross Domestic Product (GDP) of the country.

(b)(i) Calculate the total amount of depreciation of the country
(ii) Calculate the Net Domestic Product of the country.