题目

An artist went to a beautiful part of the country for a holiday, and stayed with a farmer. Every day he went out with his paints and brushes and painted from morning to evening, and then when it got dark, he went back to the farm and had a good dinner before he went to bed. At the end of his holiday he wanted to pay the farmer, but the farmer said, “No, I don’t want money… but give me one of your pictures. What is money? In a week it will all be finished, but your painting will still be here.” The artist was very pleased and thanked the farmer for saying such kind things about 若△ABC的三条中位线长分别为3，4，5，则△ABC是______三角形，它的面积为________