a british pound cost $2.00 in u.s. dollars in 2008, but $1.27 in u.s. dollars in 2017. a) was the pound weaker or stronger against the dollar? b) did the dollar appreciate or depreciate versus the pound in 2017 (compared to its original value in 2008)? c) how many british pounds does 1 usd buy in 2017? show your calculations.