Let a function f: [0,20] → Z+ be defined by f(x) = 500 – 10x. Suppose that this function is the total amount of apples (in kilograms) demanded by consumers of a particular market when the price of apples is x taka per kilogram. a. What is the amount demanded when the price x is 10 taka per kilogram? b. Denote demand by Q=f(x). Calculate the price when the demand is Q=2000. c. What is the range of the function f? d. Is f an injective function? e. Is f, an inverse function? If yes, then Calculate the inverse of f.