Calculating a country's foreign reserves?

Question

if a country has a current account deficit of 120 billion $USD, the non-reserve acct has a surplus of 80 billion $USD, and the capital account has a supposed balance of 0, how do I calculate what the change of the foreign reserves is? I don't need a direct answer, just some direction on how to do it...thanks.

Answer 1

Sounds right to me, unless it's a trick question.