The figures are invented. A diagram shows a city's market for rented flats, with monthly rent ($) on the vertical axis and quantity (thousand flats) on the horizontal axis. The equilibrium rent is $900 and the quantity is 50. The government sets a maximum rent of $750. At $750 the quantity demanded is 60 and the quantity supplied is 40. The demand curve shows a rent of $1,050 at a quantity of 40. (i) Calculate the shortage of flats. [1] (ii) Calculate the change in landlords' total monthly rental revenue. [1] (iii) Calculate the welfare loss caused by the maximum rent. [2]

HL Paper 3-style calculation (standalone practice; not an IB question).