1.The value of the Australian dollar (A$) today is $0.75. Yesterday, the value of the Australian dollar was $0.70. Calculate the percentage rate of change in the the Australian dollar. Did it appreciate or depreciate versus the dollar?

2.Assume Bulgarias currency (the lev) is worth $.19 and the Japanese yen is worth $.0088. What is the cross rate of the lev with respect to yen? That is, how many yen equal a lev?

anyone know how to do it?