请教gwd两道逻辑题

1.In the United States,of the people who moved from one state to another when they retired ,the percentage who retired to Florida hasdecreased by three percentage points over the past ten years,Since many local businesses in Florida has decreased by three percentage points over the past ten years ,Since many local businesses in Florida cater to retirees,this decline is likely to have a noticeably negative economic effect on these businesses.

weaken the argument

答案是 The total number of people who retired and moved to another state for their retirement has increased significantly over the past ten years . 不太明白答案的逻辑

2.The spacing of the four holes on a fragment of a bone flute excavated at a Neanderthal campsite is just what is required to play the third through sicth notes of the diatonic scale --the sever-note musical scale used in much of Western music since th Renaissance,Musicologists therefore hypothesize that the diatonic musical scale was developed and used thousands of years before it was adopted by Western musicians .

support the hypothesis

答案是 The cave-bear leg bone used to make the Neanderthal flute would have been long enough to make a flute capable of playing a complete diatonic scale .  非常感谢 哈哈

1.尽管退休到F的人数占总退休人数的比例下降了，但如果总退休人数总量显著上升的话，本地的经济还是增长的 量和比例不能等同

2.本文提供的论据只说明挖掘出的笛子可以演奏第3-6个音阶（非完整的七音阶），答案补充了这个漏洞

谢谢高人指点