阅读理解
Kim went to a beautiful beach on Monday with his friends. It was sunny and hot. So they had great fun playing in the water. In the afternoon，they went shopping. But the shops were crowded，they didn't really enjoy it.
The next day，it was rainy，so they went to a museum. It was boring. Kim found a small boy crying in the corner. The boy was lost. He helped the boy find his father. Kim was very happy. But he had no money for a taxi. So he had to walk back to the hotel. That made him very tired.
On Wednesday，the weather was very cool. So they played basketball. They played all morning. It was really fun.
根据短文内容，判断下列句子正误。正确的在题前括号内写“正确”，错误的写“错误”。
对于一切
成立，则a的最小值是
