foreign exchange management

Short answer type questions Assuming you are the Forex dealer and the following rates per $ (US Dollar) is quoted against SF. (Swiss Franc) Day Quote 1.6982/98 26.12.2019 27.12.2019 1.5990/7060 28.12.2019 1.7027/42 i. On which day is it cheaper to buy US $ with respect to SF? ii. How many US $ do you need to buy 1000 SF on Day 1? iii. Find out forex-spread on 27th December? iv. If you want to exchange $ 2500 for SF 4256.75 on which day it is cheapest