answer both a and b please

2. Consider a rm that hires L hours of labour services at a 1wage of 11! per hour and rents K hours of machine services at a rental rate of 1' per hour in order to produce 9 units of output in accordance 1with the production function 13 = min[lUL, 5K} . {a} Determine the rm's long-run total, average, and marginal cost functions. (h) Suppose that K is xed at 20 in the short run. Determine the rm's short-run total1 average, and marginal cost functions