I believe this question refers to the Fisher effect in international finance. I have completed a) but could do with some help for question b) particularly and the following questions. I Know the answer to b) is 1.65% but I dont know how to calculate that answer. Thanks!

Considering open economies, and these nominal interest rates for Spain: 4,03%, USA: 5,25%, and Japan: 6,10%, calculate:

a) Spot Exchange rate variation ($/euro and euro/yen)

b) Forecasted inflation rate in USA if in Japan is 2,5%

If forecasted inflation rate in Spain is 50% than in Japan, and considering nominal interest rates in Spain: 4,03% and in Japan: 6,10%, calculate:

c) Forecasted inflation rate in Spain

d) Real interest rate in each country