Using the quantity theory of money, suppose that this year's money supply is $100 billion, nominal GDP is $1 trillion, and real GDP is $250 billion. (show all your work)

a. What is the price level? What is the velocity of money?

b. Suppose that velocity is constant and the economy's output of goods and services rises by 5 percent each year. What will happen to nominal GDP and the price level next year if the Bank of Canada keeps the money supply constant?