5____2×2
8____4×2
-_________ weather it is! We can't go boating on the Xuanwu Lake.
-Don't worry. Let's go to the Science Museum instead.
山梨酸钾(化学式为C5H7COOK)是国际粮农组织和卫生组织推荐的高效安全的防腐保鲜剂,在我市海产品深加工过程中广泛使用。