Complete the following statements.(1) The willingness to have something is called ……(2) Desire, willingness to purchase and ability to pay are the three necessary conditions for ………(3) The total quantities of a commodity demanded by a particular buyer is ……(4) The sum of the total quantities of a commodity demanded by all buyers in a market is ……(5) Commodities and services satisfying the human wants directly is known as ……(6) The purchasing power of the consumer depends on ………(7) One commodity can be put to several uses, it is known as ………(8) Marshall’s law of demand describes the functional relationship between ………(9) Inferior goods like cheap bread, vegetable ghee, etc., is known as ………(10) Expensive goods such as diamonds, luxury cars are known as ……(11) When demand changes due to changes in price, it is known as ………(12) A rise in demand caused by favourable changes in other factors at same price is called ……