A：有机物一定含有碳元素，所以含有碳元素的化合物一定是有机物
B：溶液中有晶体析出时，溶质质量减小，所以溶质的质量分数一定减小
C：碱性溶液能使石蕊试液变蓝，所以能使石蕊试液变蓝的溶液一定呈碱性
D：碳酸盐与盐酸反应产生气体，所以与盐酸反应产生气体的物质一定是碳酸盐
Bill is from Australia. He lives in Sydney. He can speak French and English, but he can' t speak Chinese. He has a pen pal in the United States. Her name is Lisa and she lives in New York. Bill' s favorite sport is basketball and he can play the guitar. Lisa' s favorite sport is tennis. She can't play the guitar, but she can play the piano and sing very well.
数据26000用科学记数法表示为2.6×10n，则n的值是（ ）
若直线l：xa+yb=1（a＞0，b＞0）经过点（1，2）则直线l在x轴和y轴的截距之和的最小值是____
