Q: How is the five inch opening measured? (此处一般还有说明测量方法:measure with bag laid flat)
A: Per Rhode Island's law, the five inch opening is the diameter of the opening.
开口的周长是 L=πd=3.14×5 in.=15.7 in.,这与Canada的要求差不多,比较合理,假设周长不变,开口拉直后应是7.85;W见到的一些做法是开口拉直后直接与5in. 比较,真奇妙!