Which of the following policies help to raise interest rate unambiguously and thereby lead to appreciation of currency?

Exchange rates state the value of one currency in terms of other currencies. Which one of the following statements with respect to the exchange rate of currency is correct?

Which of the following is/are treated as artificial currency?

Which of the following is not one of the weakest currencies in the world?

In which one of the following countries is Rupee its currency?

Which among the following currencies is the costliest?