抗生素“先锋Ⅵ”为粉末状固体，每瓶含“先锋Ⅵ”0.5g，注射时应配成质量分数不高于20％的溶液，则使用时每瓶至少需加入蒸馏水质量是     (   )

芝麻、花生等硬果类食物中，含量较多的营养物质是（    ）

   In America and Canada, people also have1festival. It is2 Thanksgiving Day. It is 3the fourth Thursday of November.On that day,families get together and eat a big4.They have a lot of5for dinner.They usually eat turkeys. A turkey 6a chicken, 7 it is much bigger8a chicken.In America and Canada, many people say 9for the 10    .

函数f（x）=2cos（ωx+$\frac{\mathrm{\pi }}{4}$）在（0，$\frac{\mathrm{\pi }}{4}$）上是减函数，则ω的最大值为（　　）