题目

. Back in the fifteenth century, in a village near Nuremberg, lived a family with eighteen children. Despite the hopeless condition, two of the children, Albrecht Durer and his elder brother Albert Durer, had a dream. They both wanted to become artists. After many long discussions, the two boys finally worked out an agreement. They would toss (投掷) a coin. The loser would go down to the nearby mines and, with his earnings, support his brother while he attended the academy (大学). Then, when that brother completed his studies, in four years, he would support the other at the academy. Tossi如图所示，用相同的滑轮安装成甲、乙两种装置，分别用、匀速提升重力为、的A、B两物体，不计绳重和摩擦。若，则______；若，则______选填“”、“”或“”