    Sentence 1: Platinum prices soured to 23-year highs earlier this  year after President Bush (news - web sites ) proposed investing]  § 12 billion for research on fel cell-powered vehicles.    Sentence 2: Platinum prices’ soured to 22-year highs eater this  ear after US, President George W, Bush proposed imestig§ 12  billion for reseorch on fuel cell-powered vehicies.