Suppose that on February $1$ of the current year, the exchange rate between the Ukrainian hryvnia $($UAH$)$ and the U$.$S$.$ dollar was UAH $41/$$$.$ On February $15$ of the current year, suppose the exchange rate stood at UAH $40/$$$.$

What is the change in the value of the base currency, the dollar? Explain

What is the change in the value of the Ukrainian hryvnia $($UAH$)?$ Explain