Assume the price of a given model of Nespresso coffee machine in Boston is $150$ US dollars, and the price of the same model in Moscow is equivalent to $190$ US dollars at the prevailing Ruble$/$US dollar exchange rate. Using the concept of purchasing power parity, the Ruble is:

Group of answer choices

overvalued against the US dollar

undervalued against the US dollar

appreciating relative to the US dollar

depreciating relative to the US dollar