The exchange rate between non-fixed currencies continuously fluctuates. The following chart shows the exchange rate of the pound sterling to the Japanese yen over a period of six days. Day £:¥ Monday 1:141.014 Tuesday 1:138.650 Wednesday 1:149.890 Thursday 1:144.209 Friday 1:148.176 Saturday 1:143.008 Tina has £72.90 to turn into yen. How much greater is the amount of yen she would receive if she made her trade on the most favorable day than if she made her trade on the least favorable day? Round to the nearest whole yen. a. ¥172 b. ¥317 c. ¥819 d. ¥1,104