Costa Co. uses three identical pieces of machinery in its factory. The cash price of these machines is €8,000 each and their estimated lives four years. These were all brought into use on the same date by the following means:

a. machine 1 was rented from Brava Co. at a cost of €250 per month payable in advance and terminable at any time by either party;

b. machine 2 was rented from Blanca Co. at a cost of eight half-yearly payments in advance at €1,500;

c. machine 3 was rented from Sol Co. at a cost of six half-yearly payments in advance at €1,500.

Are the above machines rented by operating lease or by finance lease according to the current IASB rules?