Mr X owns and operates a drink stall. his annual revenue is K 200,000 and his costs are K 100,000. if Mr. X was not selling drinks he would play golf instead, which he values at K25,000.00(there are not costs of golf). X wishes to retire to play golf and wants to rent out his stall. calculate the opportunity cost of this option , if any, further , what is the minimum annual rental rate he should ask for, and give reason for answer?